mcp433x/435x mcp43x1 mcp43x2 mcp43xx mcp42xx …

2010 Microchip Technology Inc. DS22242A-page 1

MCP433X/435X

Features• Quad Resistor Network • Potentiometer or Rheostat Configuration Options• Resistor Network Resolution:

- 7-bit: 128 Resistors (129 Taps)- 8-bit: 256 Resistors (257 Taps)

• RAB Resistances Options of:- 5 k- 10 k- 50 k- 100 k

• Zero Scale to Full Scale Wiper Operation• Low Wiper Resistance: 75 (typical)• Low Tempco:

- Absolute (Rheostat): 50 ppm typical(0°C to 70°C)

- Ratiometric (Potentiometer): 15 ppm typical• SPI Serial Interface (10 MHz, Modes 0,0 and 1,1):

- High-Speed Read/Writes to wiper registers• Resistor Network Terminal Disconnect Feature

via Terminal Control (TCON) Register • Reset Input Pin• Brown-out Reset Protection (1.5V typical)• Serial Interface Inactive Current (2.5 µA typical)• High-Voltage Tolerant Digital Inputs: Up to 12.5V• Supports Split Rail Applications • Internal Weak Pull-up on all Digital Inputs • Wide Operating Voltage:

- 2.7V to 5.5V – Device Characteristics Specified

- 1.8V to 5.5V – Device Operation• Wide Bandwidth (-3 dB) Operation:

- 2 MHz (typical) for 5.0 k device • Extended Temperature Range (-40°C to +125°C)

Package Types (Top View)MCP43X1 Quad Potentiometers

TSSOP

1

2

3

4

14

151718

P2A

P

2W

6 7 8 9

12

13 RESET

SDO

NC P

0A

P1A

P1W

SDI

P3B

SCKCS

1920

P1B

P3A

P3W

VDD

MCP43X2 Quad Rheostat TSSOP

5VSS

10P

0W11 P0B

16

P2B

1234 17

181920

RESETSDO

NC

VDD567 14

1516

P0WP0B

P0AP1AP1WP1BVSS

CS

SDISCK

8910

P3BP3WP3A

1213

P2WP2A

P2B

11

1234 11

121314

P0BSDO

P0W

VDD

567 8

910

P2W

P1W

P2BP3BP3W

P1BVSS

CS

SDISCK

EP21

MCP43X1 Quad Potentiometers 4x4 QFN*

* Includes Exposed Thermal Pad (EP); see Table 3-1.

7/8-Bit Quad SPI Digital POT with Volatile Memory

MCP433X/435X

DS22242A-page 2 2010 Microchip Technology Inc.

Device Block Diagram

Device Features

Device

# of

PO

Ts

Wiper Configuration

Con

trol

In

terf

ace

Mem

ory

Type

Wip

erLo

ck

Tech

nolo

gy

POR

Wip

er

Setti

ng Resistance (typical)

# of

Tap

s

VDD Operating Range (2) RAB Options (k)

Wiper - RW ()

MCP4331 4 Potentiometer (1) SPI RAM No Mid-Scale 5.0, 10.0, 50.0, 100.0 75 129 1.8V to 5.5VMCP4332 4 Rheostat SPI RAM No Mid-Scale 5.0, 10.0, 50.0, 100.0 75 129 1.8V to 5.5VMCP4341 4 Potentiometer (1) SPI EE Yes NV Wiper 5.0, 10.0, 50.0, 100.0 75 129 2.7V to 5.5VMCP4342 4 Rheostat SPI EE Yes NV Wiper 5.0, 10.0, 50.0, 100.0 75 129 2.7V to 5.5VMCP4351 4 Potentiometer (1) SPI RAM No Mid-Scale 5.0, 10.0, 50.0, 100.0 75 257 1.8V to 5.5VMCP4352 4 Rheostat SPI RAM No Mid-Scale 5.0, 10.0, 50.0, 100.0 75 257 1.8V to 5.5VMCP4361 4 Potentiometer (1) SPI EE Yes NV Wiper 5.0, 10.0, 50.0, 100.0 75 257 2.7V to 5.5VMCP4362 4 Rheostat SPI EE Yes NV Wiper 5.0, 10.0, 50.0, 100.0 75 257 2.7V to 5.5VNote 1: Floating either terminal (A or B) allows the device to be used as a Rheostat (variable resistor).

2: Analog characteristics only tested from 2.7V to 5.5V unless otherwise noted.

Power-up/Brown-outControl

VDD

VSS

SPI SerialInterfaceModule andControlLogic

ResistorNetwork 0(Pot 0)

Wiper 0 and TCON0Register



CS SCK SDI

SDO

RESET

Memory (16x9)Wiper0 (V)Wiper1 (V)

TCON0

P0A

P0W

P0B

P1A

P1W

P1B



P2A

P2W

P2B



P3A

P3W

P3B

Wiper2 (V)Wiper3 (V)

TCON1


MCP433X/435X

1.0 ELECTRICAL CHARACTERISTICS

Absolute Maximum Ratings †Voltage on VDD with respect to VSS ..... -0.6V to +7.0VVoltage on CS, SCK, SDI, SDI/SDO, and RESET with respect to VSS ..................... -0.6V to 12.5VVoltage on all other pins (PxA, PxW, PxB and SDO) with respect to VSS ............... -0.3V to VDD + 0.3VInput clamp current, IIK (VI < 0, VI > VDD, VI > VPP ON HV pins) ........... ±20 mAOutput clamp current, IOK (VO < 0 or VO > VDD) ....................................... ±20 mAMaximum output current sunk by any Output pin ........................................................................... 25 mAMaximum output current sourced by any Output pin ........................................................................... 25 mAMaximum current out of VSS pin ...................... 100 mAMaximum current into VDD pin ......................... 100 mAMaximum current into PXA, PXW and PXB pins±2.5 mA Storage temperature ........... -65°C to +150°CAmbient temperature with power applied .......................................................... -40°C to +125°CPackage power dissipation (TA = +50°C, TJ = +150°C) TSSOP-14 ......... 1000 mWTSSOP-20......................................................1110 mWQFN-20 (4x4) ................................................ 2320 mWSoldering temperature of leads (10 seconds) .................................................... +300°CESD protection on all pins 4 kV (HBM),................................................................ 300V (MM)Maximum Junction Temperature (TJ) .............. +150°C

† Notice: Stresses above those listed under “MaximumRatings” may cause permanent damage to the device.This is a stress rating only and functional operation ofthe device at those or any other conditions above thoseindicated in the operational listings of this specificationis not implied. Exposure to maximum rating conditionsfor extended periods may affect device reliability.

MCP433X/435X


AC/DC CHARACTERISTICS

DC Characteristics

Standard Operating Conditions (unless otherwise specified)Operating Temperature –40°C TA +125°C (extended)

All parameters apply across the specified operating ranges unless noted. VDD = +2.7V to 5.5V, 5 k, 10 k, 50 k, 100 k devices. Typical specifications represent values for VDD = 5.5V, TA = +25°C.

Parameters Sym Min Typ Max Units Conditions

Supply Voltage VDD 2.7 — 5.5 V1.8 — 2.7 V Serial Interface only.

CS, SDI, SDO, SCK, RESET pin Voltage Range

VHV VSS — 12.5V V VDD 4.5V The CS pin will be at one of three input levels (VIL, VIH or VIHH). (Note 6)

VSS — VDD + 8.0V

V VDD < 4.5V

VDD Start Voltage to ensure Wiper Reset

VBOR — — 1.65 V RAM retention voltage (VRAM) < VBOR

VDD Rise Rate to ensure Power-on Reset

VDDRR (Note 9) V/ms

Delay after device exits the Reset state (VDD > VBOR)

TBORD — 10 20 µs

Supply Current(Note 10)

IDD — — 450 µA Serial Interface Active, VDD = 5.5V, CS = VIL, SCK @ 5 MHz, write all 0’s to volatile Wiper 0 (address 0h)

— 2.5 5 µA Serial Interface Inactive, CS = VIH, VDD = 5.5V

— 0.55 1 mA Serial Interface Active, VDD = 5.5V, CS = VIHH, SCK @ 5 MHz, decrement volatile Wiper 0 (address 0h)

Note 1: Resistance is defined as the resistance between terminal A to terminal B.2: INL and DNL are measured at VW with VA = VDD and VB = VSS. 3: MCP43X1 only.4: MCP43X2 only, includes VWZSE and VWFSE.5: Resistor terminals A, W and B’s polarity with respect to each other is not restricted.6: This specification by design.7: Non-linearity is affected by wiper resistance (RW), which changes significantly over voltage and

temperature. 8: The MCP43X1 is externally connected to match the configurations of the MCP43X2, and then tested.9: POR/BOR is not rate dependent.10: Supply current is independent of current through the resistor network.


MCP433X/435X

Resistance(± 20%)

RAB 4.0 5 6.0 k -502 devices(Note 1)8.0 10 12.0 k -103 devices(Note 1)

40.0 50 60.0 k -503 devices(Note 1)80.0 100 120.0 k -104 devices(Note 1)

Resolution N 257 Taps 8-bit No Missing Codes129 Taps 7-bit No Missing Codes

Step Resistance RS — RAB/ (256)

— 8-bit Note 6

— RAB/ (128)

— 7-bit Note 6

Nominal Resistance Match

(| RABWC - RABMEAN |)/

RABMEAN

— 0.2 1.50 % 5 k MCP43X1 devices only — 0.2 1.25 % 10 k— 0.2 1.0 % 50 k— 0.2 1.0 % 100 k

(| RBWWC - RBWMEAN |)/

RBWMEAN

— 0.25 1.75 % 5 k Code = Full Scale— 0.25 1.50 % 10 k— 0.25 1.25 % 50 k— 0.25 1.25 % 100 k

Wiper Resistance (Note 3, Note 4)

RW — 75 160 VDD = 5.5 V, IW = 2.0 mA, code = 00h— 75 300 VDD = 2.7 V, IW = 2.0 mA, code = 00h

Nominal Resistance Tempco

RAB/T — 50 — ppm/°C TA = -20°C to +70°C— 100 — ppm/°C TA = -40°C to +85°C— 150 — ppm/°C TA = -40°C to +125°C

Ratiometeric Tempco

VWB/T — 15 — ppm/°C Code = Mid-scale (80h or 40h)

Resistance Tracking

RTRACK Section 2.0 ppm/°C See Section 2.0 “Typical Performance Curves”

AC/DC CHARACTERISTICS (CONTINUED)

DC Characteristics






MCP433X/435X


Resistor Terminal Input Voltage Range (Terminals A, B and W)

VA,VW,VB Vss — VDD V Note 5, Note 6

Maximum current through A, W or B

IW — — 2.5 mA Worst case current through wiper when wiper is either Full Scale or Zero Scale. (Note 6)

Leakage current into A, W or B

IWL — 100 — nA MCP43X1 PxA = PxW = PxB = VSS

— 100 — nA MCP43X2 PxB = PxW = VSS


DC Characteristics







MCP433X/435X

Full Scale Error (MCP43X1 only)(8-bit code = 100h, 7-bit code = 80h)

VWFSE -6.0 -0.1 — LSb 5 k 8-bit 3.0V VDD 5.5V -4.0 -0.1 — LSb 7-bit 3.0V VDD 5.5V-3.5 -0.1 — LSb 10 k 8-bit 3.0V VDD 5.5V-2.0 -0.1 — LSb 7-bit 3.0V VDD 5.5V-0.8 -0.1 — LSb 50 k 8-bit 3.0V VDD 5.5V-0.5 -0.1 — LSb 7-bit 3.0V VDD 5.5V-0.5 -0.1 — LSb 100 k 8-bit 3.0V VDD 5.5V-0.5 -0.1 — LSb 7-bit 3.0V VDD 5.5V

Zero Scale Error (MCP43X1 only)(8-bit code = 00h, 7-bit code = 00h)

VWZSE — +0.1 +6.0 LSb 5 k 8-bit 3.0V VDD 5.5V— +0.1 +3.0 LSb 7-bit 3.0V VDD 5.5V— +0.1 +3.5 LSb 10 k 8-bit 3.0V VDD 5.5V— +0.1 +2.0 LSb 7-bit 3.0V VDD 5.5V— +0.1 +0.8 LSb 50 k 8-bit 3.0V VDD 5.5V— +0.1 +0.5 LSb 7-bit 3.0V VDD 5.5V— +0.1 +0.5 LSb 100 k 8-bit 3.0V VDD 5.5V— +0.1 +0.5 LSb 7-bit 3.0V VDD 5.5V

Potentiometer Integral Non-linearity

INL -1 ±0.5 +1 LSb 8-bit 3.0V VDD 5.5V MCP43X1 devices only (Note 2)

-0.5 ±0.25 +0.5 LSb 7-bit

Potentiometer Differential Non-linearity

DNL -0.5 ±0.25 +0.5 LSb 8-bit 3.0V VDD 5.5V MCP43X1 devices only (Note 2)

-0.25 ±0.125 +0.25 LSb 7-bit

Bandwidth -3 dB (See Figure 2-92, load = 30 pF)

BW — 2 — MHz 5 k 8-bit Code = 80h — 2 — MHz 7-bit Code = 40h — 1 — MHz 10 k 8-bit Code = 80h — 1 — MHz 7-bit Code = 40h — 200 — kHz 50 k 8-bit Code = 80h — 200 — kHz 7-bit Code = 40h — 100 — kHz 100 k 8-bit Code = 80h — 100 — kHz 7-bit Code = 40h


DC Characteristics






MCP433X/435X


Rheostat Integral Non-linearity MCP43X1 (Note 4, Note 8) MCP43X2 devices only (Note 4)

R-INL -1.5 ±0.5 +1.5 LSb 5 k 8-bit 5.5V, IW = 900 µA-8.25 +4.5 +8.25 LSb 3.0V, IW = 480 µA

(Note 7)Section 2.0 1.8V, IW = 190 µA

-1.125 ±0.5 +1.125 LSb 7-bit 5.5V, IW = 900 µA -6.0 +4.5 +6.0 LSb 3.0V, IW = 480 µA


-1.5 ±0.5 +1.5 LSb 10 k 8-bit 5.5V, IW = 450 µA-5.5 +2.5 +5.5 LSb 3.0V, IW = 240 µA


-1.125 ±0.5 +1.125 LSb 7-bit 5.5V, IW = 450 µA-4.0 +2.5 +4.0 LSb 3.0V, IW = 240 µA


-1.5 ±0.5 +1.5 LSb 50 k 8-bit 5.5V, IW = 90 µA-2.0 +1 +2.0 LSb 3.0V, IW = 48 µA


-1.125 ±0.5 +1.125 LSb 7-bit 5.5V, IW = 90 µA-1.5 +1 +1.5 LSb 3.0V, IW = 48 µA







DC Characteristics







MCP433X/435X

Rheostat Differential Non-linearity MCP43X1 (Note 4, Note 8) MCP43X2 devices only (Note 4)

R-DNL -0.5 ±0.25 +0.5 LSb 5 k 8-bit 5.5V, IW = 900 µA-1.0 +0.5 +1.0 LSb 3.0V, IW = 480 µA








-0.5 ±0.25 +0.5 LSb 50 k 8-bit 5.5V, IW = 90 µA-0.5 ±0.25 +0.5 LSb 3.0V, IW = 48 µA


-0.375 ±0.25 +0.375 LSb 7-bit 5.5V, IW = 90 µA-0.375 ±0.25 +0.375 LSb 3.0V, IW = 48 µA


-0.5 ±0.25 +0.5 LSb 100 k 8-bit 5.5V, IW = 45 µA-0.5 ±0.25 +0.5 LSb 3.0V, IW = 24 µA


-0.375 ±0.25 +0.375 LSb 7-bit 5.5V, IW = 45 µA-0.375 ±0.25 +0.375 LSb 3.0V, IW = 24 µA



DC Characteristics






MCP433X/435X


Capacitance (PA) CAW — 75 — pF f =1 MHz, Code = Full Scale Capacitance (Pw) CW — 120 — pF f =1 MHz, Code = Full Scale Capacitance (PB) CBW — 75 — pF f =1 MHz, Code = Full Scale

Digital Inputs/Outputs (CS, SDI, SDO, SCK, WP, RESET)Schmitt Trigger High Input Threshold

VIH 0.45 VDD

— — V 2.7V VDD 5.5V (Allows 2.7V Digital VDD with 5V Analog VDD)

0.5 VDD — — V 1.8V VDD 2.7VSchmitt Trigger Low Input Threshold

VIL — — 0.2VDD V

Hysteresis of Schmitt Trigger Inputs

VHYS — 0.1VDD — V

High Voltage Input Entry Voltage

VIHH 8.5 — 12.5 (6) V

High Voltage Input Exit Voltage

VIHH — — VDD + 0.8V

V

High Voltage Limit VMAX — — 12.5 (6) V Pin can tolerate VMAX or less. Output Low Voltage (SDO)

VOL VSS — 0.3VDD V IOL = 5 mA, VDD = 5.5V VSS — 0.3VDD V IOL = 1 mA, VDD = 1.8V

Output High Voltage (SDO)

VOH 0.7VDD — VDD V IOH = -2.5 mA, VDD = 5.5V 0.7VDD — VDD V IOL = -1 mA, VDD = 1.8V


DC Characteristics







MCP433X/435X

Weak Pull-up Current

IPU — — 1.75 mA Internal VDD pull-up, VIHH pull-down, VDD = 5.5V, VCS = 12.5V

— 170 — µA CS pin, VDD = 5.5V, VCS = 3V CS Pull-up/Pull-down Resistance

RCS — 16 — k VDD = 5.5V, VCS = 3V

RESET Pull-up Resistance

RRESET — 16 — k VDD = 5.5V, VRESET = 0V

Input Leakage Current

IIL -1 — 1 µA VIN = VDD (all pins) and VIN = VSS (all pins except RESET)

Pin Capacitance CIN, COUT — 10 — pF fC = 20 MHzRAM (Wiper, TCON) ValueValue Range N 0h — 1FFh hex 8-bit device

0h — 1FFh hex 7-bit deviceTCON POR/BOR Setting

1FF hex All terminals connected

Wiper POR/BOR Setting

N 080h hex 8-bit 040h hex 7-bit

Power RequirementsPower Supply Sensitivity (MCP43X1)

PSS — 0.0015 0.0035 %/% 8-bit VDD = 2.7V to 5.5V, VA = 2.7V, Code = 80h

— 0.0015 0.0035 %/% 7-bit VDD = 2.7V to 5.5V, VA = 2.7V, Code = 40h


DC Characteristics






MCP433X/435X


1.1 SPI Mode Timing Waveforms and Requirements

FIGURE 1-1: Reset Waveforms. TABLE 1-1: RESET TIMING

Timing Characteristics




RESET pulse width tRST 50 — — ns

RESET rising edge normal mode (Wiper driving and SPI interface operational)

tRSTD — — 20 ns

RESET

SCK

tRST tRSTD

Wx


MCP433X/435X

FIGURE 1-2: SPI Timing Waveform (Mode = 11).

TABLE 1-2: SPI REQUIREMENTS (MODE = 11)# Characteristic Symbol Min Max Units Conditions

SCK Input Frequency FSCK — 10 MHz VDD = 2.7V to 5.5V— 1 MHz VDD = 1.8V to 2.7V

70 CS Active (VIL or VIHH) to SCK input TcsA2scH 60 — ns71 SCK input high time TscH 45 — ns VDD = 2.7V to 5.5V

500 — ns VDD = 1.8V to 2.7V72 SCK input low time TscL 45 — ns VDD = 2.7V to 5.5V

500 — ns VDD = 1.8V to 2.7V73 Setup time of SDI input to SCK edge TDIV2scH 10 — ns VDD = 2.7V to 5.5V

20 — ns VDD = 1.8V to 2.7V74 Hold time of SDI input from SCK edge TscH2DIL 20 — ns77 CS Inactive (VIH) to SDO output high-impedance TcsH2DOZ — 50 ns Note 180 SDO data output valid after SCK edge TscL2DOV — 70 ns VDD = 2.7V to 5.5V

170 ns VDD = 1.8V to 2.7V83 CS Inactive (VIH) after SCK edge TscH2csI 100 — ns VDD = 2.7V to 5.5V

1 ms VDD = 1.8V to 2.7V84 Hold time of CS Inactive (VIH) to

CS Active (VIL or VIHH)TcsA2csI 50 — ns

Note 1: This specification by design.

CS

SCK

SDO

SDI

70

71

72

7374

75, 76 77

787980

SDI

MSb LSbBIT6 - - - - - -1

MSb IN BIT6 - - - -1 LSb IN

83

84

VIH

VIL

VIHH VIH

MCP433X/435X


FIGURE 1-3: SPI Timing Waveform (Mode = 00).

TABLE 1-3: SPI REQUIREMENTS (MODE = 00)# Characteristic Symbol Min Max Units Conditions

SCK Input Frequency FSCK — 10 MHz VDD = 2.7V to 5.5V— 1 MHz VDD = 1.8V to 2.7V

70 CS Active (VIL or VIHH) to SCK input TcsA2scH 60 — ns71 SCK input high time TscH 45 — ns VDD = 2.7V to 5.5V

500 — ns VDD = 1.8V to 2.7V72 SCK input low time TscL 45 — ns VDD = 2.7V to 5.5V

500 — ns VDD = 1.8V to 2.7V73 Setup time of SDI input to SCK edge TDIV2scH 10 — ns VDD = 2.7V to 5.5V

20 — ns VDD = 1.8V to 2.7V74 Hold time of SDI input from SCK edge TscH2DIL 20 — ns77 CS Inactive (VIH) to SDO output high-impedance TcsH2DOZ — 50 ns Note 180 SDO data output valid after SCK edge TscL2DOV — 70 ns VDD = 2.7V to 5.5V

170 ns VDD = 1.8V to 2.7V82 SDO data output valid after

CS Active (VIL or VIHH)TssL2doV — 85 ns

83 CS Inactive (VIH) after SCK edge TscH2csI 100 — ns VDD = 2.7V to 5.5V1 ms VDD = 1.8V to 2.7V

84 Hold time of CS Inactive (VIH) to CS Active (VIL or VIHH)

TcsA2csI 50 — ns

Note 1: This specification by design.

CS

SCK

SDO

SDI

70

71 72

82

SDI

74

75, 76

MSb BIT6 - - - - - -1 LSb

77

MSb IN BIT6 - - - -1 LSb IN

80

83

84

73

VIH

VIL

VIHH VIH


MCP433X/435X

TEMPERATURE CHARACTERISTICSElectrical Specifications: Unless otherwise indicated, VDD = +2.7V to +5.5V, VSS = GND.


Temperature RangesSpecified Temperature Range TA -40 — +125 °COperating Temperature Range TA -40 — +125 °CStorage Temperature Range TA -65 — +150 °CThermal Package ResistancesThermal Resistance, 14L-TSSOP JA — 100 — °C/WThermal Resistance, 20L-QFN JA — 43 — °C/WThermal Resistance, 20L-TSSOP JA — 90 — °C/W

MCP433X/435X


NOTES:


MCP433X/435X

2.0 TYPICAL PERFORMANCE CURVES

Note: Unless otherwise indicated, TA = +25°C, VDD = 5V, VSS = 0V.

FIGURE 2-1: Device Current (IDD) vs. SPI Frequency (fSCK) and Ambient Temperature (VDD = 2.7V and 5.5V).

FIGURE 2-2: Device Current (ISHDN) and VDD. (CS = VDD) vs. Ambient Temperature.

FIGURE 2-3: CS Pull-up/Pull-down Resistance (RCS) and Current (ICS) vs. CS Input Voltage (VCS) (VDD = 5.5V).

FIGURE 2-4: CS High Input Entry/Exit Threshold vs. Ambient Temperature and VDD.

Note: The graphs and tables provided following this note are a statistical summary based on a limited number ofsamples and are provided for informational purposes only. The performance characteristics listed hereinare not tested or guaranteed. In some graphs or tables, the data presented may be outside the specifiedoperating range (e.g., outside specified power supply range) and therefore outside the warranted range.

050

100150200250300350400450500550600650700

0.00 2.00 4.00 6.00 8.00 10.00 12.00fSCK (MHz)

Ope

ratin

g C

urre

nt (I

DD) (

μA) 2.7V -40°C

2.7V 25°C2.7V 85°C2.7V 125°C5.5V -40°C5.5V 25°C5.5V 85°C5.5V 125°C

0.0

0.5

1.0

1.5

2.0

2.5

3.0

-40 25 85 125Ambient Temperature (°C)

Stan

dby

Cur

rent

(Ist

by) (

μA)

5.5V

2.7V

0

50

100

150

200

250

2 3 4 5 6 7 8 9 10VCS (V)

RC

S (k

Ohm

s)

-1000-800-600-400-20002004006008001000

I CS

(μA

)ICS

RCS

0

2

4

6

8

10

12

-40 -20 0 20 40 60 80 100 120Ambient Temperature (°C)

CS

V PP

Thre

shol

d (V

)

2.7V Exit

5.5V Exit

2.7V Entry5.5V Entry

MCP433X/435X



FIGURE 2-5: 5 k Pot Mode – RW (), INL (LSb), DNL (LSb) vs. Wiper Setting and Ambient Temperature (VDD = 5.5V).



FIGURE 2-8: 5 k Rheo Mode – RW (), INL (LSb), DNL (LSb) vs. Wiper Setting and Ambient Temperature (VDD = 5.5V, IW = 900 µA).



20

40

60

80

100

120

0 32 64 96 128 160 192 224 256Wiper Setting (decimal)

Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

Erro

r (LS

b)

-40C Rw 25C Rw 85C Rw 125C Rw-40C INL 25C INL 85C INL 125C INL-40C DNL 25C DNL 85C DNL 125C DNL

INLDNL

RW-40°C 25°C85°C125°C

20

60

100

140

180

220

260

300


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

Erro

r (LS

b)


INLDNL

-40°C 25°C85°C

RW

125°C

0

500

1000

1500

2000

2500

0 64 128 192 256Wiper Setting (decimal)

Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

Erro

r (LS

b)


INL

DNLRW

Note: See Appendix B: for additional infor-mation of RW resistance variation char-acteristics for VDD > 2.7V.

20

40

60

80

100

120


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-1.25

-0.75

-0.25

0.25

0.75

1.25

Erro

r (LS

b)


INL

DNL

RW

-40°C25°C85°C125°C

20

60

100

140

180

220

260

300


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-2

0

2

4

6

Erro

r (LS

b)


INL

DNL

RW

-40°C25°C

85°C125°C

0

500

1000

1500

2000

2500


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-2

18

38

58

78

98

118

Erro

r (LS

b)


INL

DNLRW



MCP433X/435XNote: Unless otherwise indicated, TA = +25°C, VDD = 5V, VSS = 0V.

FIGURE 2-11: 5 k – Nominal Resistance (RAB) () vs. Ambient Temperature and VDD.

FIGURE 2-12: 5 k – RWB () vs. Wiper Setting and Ambient Temperature (VDD = 5.5V, IW = 190 µA).



5050

5100

5150

5200

5250

5300

-40 0 40 80 120Ambient Temperature (°C)

Nom

inal

Res

ista

nce

(RA

B)(O

hms)

2.7V

5.5V

1.8V

0

1000

2000

3000

4000

5000

6000

0 32 64 96 128 160 192 224 256Wiper Code

Res

ista

nce

(�)

-40C+25C+85C+125C

0

1000

2000

3000

4000

5000

6000

0 32 64 96 128 160 192 224 256Wiper Code

Res

ista

nce

(�)

-40C+25C+85C+125C

0

1000

2000

3000

4000

5000

6000

7000

0 32 64 96 128 160 192 224 256Wiper Code

Res

ista

nce

(�)

-40C+25C+85C+125C


MCP433X/435X



FIGURE 2-15: 5 k – Worst Case RBW from Average RBW (RBW0-RBW3) Error (%) vs. Wiper Setting and Temperature (VDD = 5.5V, IW = 190 µA).



FIGURE 2-18: 5 k – RWB PPM/°C vs. Wiper Setting. (RBW(code=n, 125°C)-RBW(code=n, -40°C) )/RBW(code = 256, 25°C)/165°C * 1,000,000) (VDD = 5.5V, IW = 190 µA).



-2.50%

-1.50%

-0.50%

0.50%

1.50%

2.50%

0 32 64 96 128 160 192 224 256Wiper Code

Erro

r %

-40C+25C+85C+125C

-2.50%

-1.50%

-0.50%

0.50%

1.50%

2.50%

0 32 64 96 128 160 192 224 256

Wiper Code

Erro

r %

-40C+25C+85C+125C

-7.00%

-6.00%

-5.00%

-4.00%

-3.00%

-2.00%

-1.00%

0.00%

1.00%

2.00%

0 32 64 96 128 160 192 224 256

Wiper Code

Erro

r %

-40C+25C+85C+125C


40

42

44

46

48

50

52

54

0 32 64 96 128 160 192 224 256Wiper Code

PPM

/ °C

CH0 CH1CH2 CH3

60

65

70

75

80

85

90

95

100

0 32 64 96 128 160 192 224 256Wiper Code

PPM

/ °C

CH0 CH1CH2 CH3

-2000

-1500

-1000

-500

0

500

0 32 64 96 128 160 192 224 256Wiper Code

PPM

/ °C

CH0 CH1CH2 CH3




FIGURE 2-21: 5 k – Low-Voltage Decrement Wiper Settling Time (VDD = 5.5V) (1 µs/Div).


FIGURE 2-23: 5 k – Power-Up Wiper Response Time (20 ms/Div).

FIGURE 2-24: 5 k – Low-Voltage Increment Wiper Settling Time (VDD = 5.5V) (1 µs/Div).


MCP433X/435X









20

40

60

80

100

120


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

Erro

r (LS

b)


INLDNL

RW-40°C25°C

85°C125°C

20

60

100

140

180

220

260

300


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

Erro

r (LS

b)


INLDNL

RW

-40°C25°C85°C125°C

0500

1000150020002500300035004000


Wip

er R

esis

tanc

e (R

W)(o

hms)

-0.3-0.2-0.100.10.20.30.40.50.6

Erro

r (LS

b)


INL

DNL

RW


20

40

60

80

100

120


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-1

-0.5

0

0.5

1

Erro

r (LS

b)


INL

DNLRW-40°C25°C85°C

125°C

20

60

100

140

180

220

260

300


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-2

-1

0

1

2

3

4

Erro

r (LS

b)


INL

DNL RW-40°C25°C85°C125°C

0

500

1000

1500

2000

2500

3000

3500

4000


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-28182838485868788898

Erro

r (LS

b)

-40C Rw 25C Rw 85C Rw125C Rw -40C INL 25C INL85C INL 125C INL -40C DNL25C DNL 85C DNL 125C DNL

INL

DNLRW








985099009950

10000100501010010150102001025010300


Nom

inal

Res

ista

nce

(RA

B)(O

hms)

2.7V

5.5V

1.8V

0

2000

4000

6000

8000

10000

12000

0 32 64 96 128 160 192 224 256Wiper Code

Res

ista

nce

(�)

-40C+25C+85C+125C

0

2000

4000

6000

8000

10000

12000

0 32 64 96 128 160 192 224 256Wiper Code

Res

ista

nce

(�)

-40C+25C+85C+125C

0

2000

4000

6000

8000

10000

12000

0 32 64 96 128 160 192 224 256Wiper Code

Res

ista

nce

(�)

-40C+25C+85C+125C


MCP433X/435X









-1.50%

-1.00%

-0.50%

0.00%

0.50%

1.00%

1.50%

0 32 64 96 128 160 192 224 256Wiper Code

Erro

r %

-40C +25C+85C +125C

-1.50%

-1.00%

-0.50%

0.00%

0.50%

1.00%

1.50%

0 32 64 96 128 160 192 224 256Wiper Code

Erro

r %

-40C +25C+85C +125C

-1.50%

-1.00%

-0.50%

0.00%

0.50%

1.00%

1.50%

0 32 64 96 128 160 192 224 256

Wiper Code

Erro

r %

-40C +25C+85C +125C


10

15

20

25

30

35

40

45

50

0 32 64 96 128 160 192 224 256Wiper Code

PPM

/ °C

CH0 CH1CH2 CH3

20

25

30

35

40

45

50

55

60

0 32 64 96 128 160 192 224 256Wiper Code

PPM

/ °C

CH0 CH1CH2 CH3

-1400

-1200

-1000

-800

-600

-400

-200

0

200

0 32 64 96 128 160 192 224 256Wiper Code

PPM

/ °C

CH0 CH1CH2 CH3


MCP433X/435X









20

40

60

80

100

120


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

Erro

r (LS

b)


INLDNL

RW-40°C

25°C85°C125°C

20

60

100

140

180

220

260

300


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

Erro

r (LS

b)


INLDNL

RW

-40°C25°C85°C125°C


0100020003000400050006000700080009000

100001100012000130001400015000


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-0.5-0.4-0.3-0.2-0.100.10.20.30.40.5

Erro

r (LS

b)


INL

DNL

RW

20

40

60

80

100

120


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

Erro

r (LS

b)


INLDNL

RW-40°C25°C85°C125°C

20

60

100

140

180

220

260

300


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-1

-0.75

-0.5

-0.25

0

0.25

0.5

0.75

1

Erro

r (LS

b)


INL

DNL

RW

-40°C25°C85°C125°C

0100020003000400050006000700080009000

100001100012000130001400015000


Wip

er R

esis

tanc

e (R

w)

(ohm

s)

-1.53.58.513.518.523.528.533.538.543.548.553.558.563.568.573.578.5

Erro

r (LS

b)


INL

DNL

RW








49000

49500

50000

50500

51000

51500

52000

52500


Nom

inal

Res

ista

nce

(RA

B)(O

hms)

2.7V

1.8V

5.5V

0

10000

20000

30000

40000

50000

60000

0 32 64 96 128 160 192 224 256Wiper Code

Res

ista

nce

(�)

-40C+25C+85C+125C

0

10000

20000

30000

40000

50000

60000

0 32 64 96 128 160 192 224 256Wiper Code

Res

ista

nce

(�)

-40C+25C+85C+125C

0

10000

20000

30000

40000

50000

60000

0 32 64 96 128 160 192 224 256Wiper Code

Res

ista

nce

(�)

-40C+25C+85C+125C


MCP433X/435X









-1.00%

0.00%

1.00%

2.00%

3.00%

4.00%

5.00%

6.00%

7.00%

0 32 64 96 128 160 192 224 256Wiper Code

Erro

r %

-40C +25C+85C +125C

-2.00%

-1.00%

0.00%

1.00%

2.00%

3.00%

4.00%

0 32 64 96 128 160 192 224 256Wiper Code

Erro

r %

-40C +25C+85C +125C

-1.50%

-0.50%

0.50%

1.50%

2.50%

3.50%

0 32 64 96 128 160 192 224 256Wiper Code

Erro

r %

-40C +25C+85C +125C


-3-2-101234567

0 32 64 96 128 160 192 224 256Wiper Code

PPM

/ °C

CH0 CH1CH2 CH3

-2

0

2

4

6

8

10

12

0 32 64 96 128 160 192 224 256Wiper Code

PPM

/ °C

CH0 CH1CH2 CH3

-1400

-1200

-1000

-800

-600

-400

-200

0

200

0 32 64 96 128 160 192 224 256Wiper Code

PPM

/ °C

CH0 CH1CH2 CH3


MCP433X/435X









20

40

60

80

100

120


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-0.2

-0.1

0

0.1

0.2

Erro

r (LS

b)


INLDNL

RW-40°C25°C

85°C125°C

20

60

100

140

180

220

260

300


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-0.2

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

0.2

Erro

r (LS

b)


INLDNL

RW

-40°C25°C85°C125°C

0

5000

10000

15000

20000

25000


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-0.35

-0.25

-0.15

-0.05

0.05

0.15

0.25

0.35

Erro

r (LS

b)


INL

DNL

RW


20

40

60

80

100

120


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

Erro

r (LS

b)


INL

DNL

RW-40°C25°C85°C125°C

20

60

100

140

180

220

260

300


Wip

er R

esis

tanc

e (R

w)

(ohm

s)

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

Erro

r (LS

b)


INL

DNL

RW

-40°C25°C85°C125°C

0

5000

10000

15000

20000

25000


Wip

er R

esis

tanc

e (R

W)

(ohm

s)

-14914192429343944495459

Erro

r (LS

b)


INL

DNL

RW








985009900099500

100000100500101000101500102000102500103000103500


Nom

inal

Res

ista

nce

(RA

B)(O

hms)

2.7V

5.5V

1.8V

0

20000

40000

60000

80000

100000

120000

0 32 64 96 128 160 192 224 256Wiper Code

Res

ista

nce

(�)

-40C+25C+85C+125C

0

20000

40000

60000

80000

100000

120000

0 32 64 96 128 160 192 224 256Wiper Code

Res

ista

nce

(�)

-40C+25C+85C+125C

0

20000

40000

60000

80000

100000

120000

0 32 64 96 128 160 192 224 256Wiper Code

Res

ista

nce

(�)

-40C+25C+85C+125C


MCP433X/435X









-1.00%0.00%1.00%2.00%3.00%4.00%5.00%6.00%7.00%8.00%9.00%

10.00%11.00%12.00%13.00%14.00%

0 32 64 96 128 160 192 224 256Wiper Code

Erro

r %

-40C +25C+85C +125C

-1.00%

0.00%

1.00%

2.00%

3.00%

4.00%

5.00%

6.00%

7.00%

0 32 64 96 128 160 192 224 256Wiper Code

Erro

r %

-40C +25C+85C +125C

-1.00%

0.00%

1.00%

2.00%

3.00%

4.00%

5.00%

6.00%

0 32 64 96 128 160 192 224 256Wiper Code

Erro

r %

-40C +25C+85C +125C


02468

10121416

0 32 64 96 128 160 192 224 256Wiper Code

PPM

/ °C

CH0 CH1CH2 CH3

02468

1012141618

0 32 64 96 128 160 192 224 256Wiper Code

PPM

/ °C

CH0 CH1CH2 CH3

-1200

-1000

-800

-600

-400

-200

0

200

0 32 64 96 128 160 192 224 256Wiper Code

PPM

/ °C

CH0 CH1CH2 CH3


MCP433X/435X



FIGURE 2-86: VIH (SDI, SCK, CS, and RESET) vs. VDD and Temperature.

FIGURE 2-87: VIL (SDI, SCK, CS, and RESET) vs. VDD and Temperature.

FIGURE 2-88: IOH (SDO) vs. VDD and Temperature.

FIGURE 2-89: IOL (SDO) vs. VDD and Temperature.

1

1.2

1.4

1.6

1.8

2

2.2

2.4

-40 0 40 80 120

Temperature (°C)

V IH (V

)

5.5V

2.7V

0.60.70.80.9

11.11.21.31.4

-40 0 40 80 120

Temperature (°C)

V IL (

V)

5.5V

2.7V

-45-40-35-30-25-20-15-10-50

-40 0 40 80 120

Temperature (°C)

I OH (m

A)

5.5V

2.7V

05

101520253035404550

-40 0 40 80 120

Temperature (°C)

I OL (

mA

)

5.5V

2.7V


MCP433X/435XNote: Unless otherwise indicated, TA = +25°C,VDD = 5V, VSS = 0V.

FIGURE 2-90: POR/BOR Trip point vs. VDD and Temperature.

FIGURE 2-91: SCK Input Frequency vs. Voltage and Temperature.

2.1 Test Circuits

FIGURE 2-92: -3 db Gain vs. Frequency Measurement.

FIGURE 2-93: RBW and RW Measurement.

0

0.4

0.8

1.2

1.6

2

-40 0 40 80 120

Temperature (°C)

V DD (V

)

13.413.513.613.713.813.914.014.114.2

-40 0 40 80 120

Temperature (°C)

fsck

(MH

z)

2.7V

5.5V

+

-

VOUT

2.5V DC

+5V

A

B

W

OffsetGND

VIN

A

B

W

IW

VW

floating

RBW = VW / IW

VA

VB RW = (VW - VA) / IW

MCP433X/435X


NOTES:


MCP433X/435X

3.0 PIN DESCRIPTIONSThe descriptions of the pins are listed in Table 3-1.Additional descriptions of the device pins follows.

TABLE 3-1: PINOUT DESCRIPTION FOR THE MCP433X/435XPin Weak

Pull-up/down

(Note 1)

Standard FunctionTSSOP QFNSymbol I/O Buffer

Type14L 20L 20L

— 1 19 P3A A Analog No Potentiometer 3 Terminal A

1 2 20 P3W A Analog No Potentiometer 3 Wiper Terminal

2 3 1 P3B A Analog No Potentiometer 3 Terminal B

3 4 2 CS I HV w/ST “smart” SPI Chip Select Input

4 5 3 SCK I HV w/ST “smart” SPI Clock Input

5 6 4 SDI I HV w/ST “smart” SPI Serial Data Input

6 7 5 VSS — P — Ground







— 14 12 NC I I — No Connect

— 15 13 RESET I HV w/ST Yes Hardware Reset Pin

11 16 14 SDO O O No SPI Serial Data Output

12 17 15 VDD — P — Positive Power Supply Input




— — 21 EP — — — Exposed Pad. (Note 2)Legend: HV w/ST = High Voltage tolerant input (with Schmitt trigger input)

A = Analog pins (Potentiometer terminals) I = digital input (high Z) O = digital output I/O = Input / Output P = Power

Note 1: The pin’s “smart” pull-up shuts off while the pin is forced low. This is done to reduce the standby and shutdown current.

2: The QFN package has a contact on the bottom of the package. This contact is conductively connected to the die substrate, and therefore should be unconnected or connected to the same ground as the device’s VSS pin.

MCP433X/435X


3.1 Chip Select (CS)The CS pin is the serial interface’s chip select input.Forcing the CS pin to VIL enables the serial commands.Forcing the CS pin to VIHH enables the high-voltageserial commands.

3.2 Serial Clock (SCK)The SCK pin is the serial interface's Serial Clock pin.This pin is connected to the host controllers SCK pin.The MCP43XX is an SPI slave device, so it’s SCK pinis an input only pin.

3.3 Serial Data In (SDI) The SDI pin is the serial interfaces Serial Data In pin.This pin is connected to the host controllers SDO pin.

3.4 Ground (VSS)The VSS pin is the device ground reference.

3.5 Potentiometer Terminal BThe terminal B pin is connected to the internalpotentiometer’s terminal B.

The potentiometer’s terminal B is the fixed connectionto the zero scale wiper value of the digitalpotentiometer. This corresponds to a wiper value of0x00 for both 7-bit and 8-bit devices.

The terminal B pin does not have a polarity relative tothe terminal W or A pins. The terminal B pin cansupport both positive and negative current. The voltageon terminal B must be between VSS and VDD.

MCP43XX devices have four terminal B pins, one foreach resistor network.

3.6 Potentiometer Wiper (W) Terminal The terminal W pin is connected to the internalpotentiometer’s terminal W (the wiper). The wiperterminal is the adjustable terminal of the digitalpotentiometer. The terminal W pin does not have apolarity relative to terminals A or B pins. The terminalW pin can support both positive and negative current.The voltage on terminal W must be between VSS andVDD.

MCP43XX devices have four terminal W pins, one foreach resistor network.

3.7 Potentiometer Terminal AThe terminal A pin is available on the MCP43X1devices, and is connected to the internalpotentiometer’s terminal A.

The potentiometer’s terminal A is the fixed connectionto the full scale wiper value of the digital potentiometer.This corresponds to a wiper value of 0x100 for 8-bitdevices or 0x80 for 7-bit devices.

The terminal A pin does not have a polarity relative tothe terminal W or B pins. The terminal A pin cansupport both positive and negative current. The voltageon terminal A must be between VSS and VDD.

The terminal A pin is not available on the MCP43X2devices, and the internally terminal A signal is floating.

MCP43X1 devices have four terminal A pins, one foreach resistor network.

3.8 Not Connected (NC) The NC pin is not used.

3.9 Reset (RESET) The RESET pin is used to force the device into thePOR/BOR state.

3.10 Serial Data Out (SDO) The SDO pin is the serial interfaces Serial Data Out pin.This pin is connected to the host controllers SDI pin.

This pin allows the host controller to read the digitalpotentiometers registers, or monitor the state of thecommand error bit.

3.11 Positive Power Supply Input (VDD)The VDD pin is the device’s positive power supply input.The input power supply is relative to VSS.

While the devices VDD is less than Vmin (2.7V), theelectrical performance of the device may not meet thedata sheet specifications.

3.12 Exposed Pad (EP)This pad is conductively connected to the device'ssubstrate. This pad should be tied to the same potentialas the VSS pin (or left unconnected). This pad could beused to assist as a heat sink for the device whenconnected to a PCB heat sink.

https://www.application-datasheet.com/


MCP433X/435X

4.0 FUNCTIONAL OVERVIEWThis data sheet covers a family of four volatile DigitalPotentiometer and Rheostat devices that will bereferred to as MCP43XX. The MCP43X1 devices arethe Potentiometer configuration, while the MCP43X2devices are the Rheostat configuration.

As the Device Block Diagram shows, there are fourmain functional blocks. These are:

• POR/BOR and Reset Operation• Memory Map• Resistor Network• Serial Interface (SPI)The POR/BOR operation and the Memory Map arediscussed in this section and the Resistor Network andSPI operation are described in their own sections. TheDevice Commands are discussed in Section 7.0.

4.1 POR/BOR and Reset OperationThe Power-on Reset is the case where the device ishaving power applied to it from VSS. The Brown-outReset occurs when a device had power applied to it,and that power (voltage) drops below the specifiedrange.

The devices RAM retention voltage (VRAM) is lowerthan the POR/BOR voltage trip point (VPOR/VBOR). Themaximum VPOR/VBOR voltage is less than 1.8V.

When VPOR/VBOR < VDD < 2.7V, the analog electricalperformance may not meet the data sheetspecifications. In this region, the device is capable ofincrementing, decrementing, reading and writing to itsvolatile memory, if the proper serial command isexecuted.

When VDD < VPOR/VBOR or the RESET pin is Low, thepin weak pull-ups are enabled.

4.1.1 POWER-ON RESET When the device powers up, the device VDD will crossthe VPOR/VBOR voltage. Once the VDD voltage crossesthe VPOR/VBOR voltage, the following happens:

• Volatile wiper register is loaded with the default value

• The TCON registers are loaded with their default value

• The device is capable of digital operation

4.1.2 BROWN-OUT RESET When the device powers down, the device VDD willcross the VPOR/VBOR voltage.

Once the VDD voltage decreases below the VPOR/VBORvoltage the following happens:

• Serial Interface is disabled

If the VDD voltage decreases below the VRAM voltage,the following happens:

• Volatile wiper registers may become corrupted• TCON registers may become corrupted

As the voltage recovers above the VPOR/VBOR voltage,the operation is the same as Power-on Reset (seeSection 4.1.1 “Power-on Reset”).

Serial commands not completed due to a brown-outcondition may cause the memory location to becomecorrupted.

4.1.3 RESET PIN

The RESET pin can be used to force the device intothe POR/BOR state of the device. When the RESETpin is forced Low, the device is forced into the Resetstate. This means that the TCON registers are forcedto their default values and the volatile wiper registersare loaded with the default value. Also the SPIinterface is disabled.

This feature allows a hardware method for all registersto be updated to the default value at the same time.

4.1.4 INTERACTION OF RESET PIN AND BOR/POR CIRCUITRY

Figure 4-1 shows how the RESET pin signal and thePOR/BOR signal interact to control the hardware Resetstate of the device.

FIGURE 4-1: POR/BOR Signal and RESET Pin Interaction.

RESET (from pin)

POR/BOR signal Device Reset



MCP433X/435X


4.2 Memory MapThe device memory supports 16 locations that are9-bits wide (16x9 bits). This memory space containsonly volatile locations (see Table 4-2).

4.2.1 VOLATILE MEMORY (RAM)There are six volatile memory locations. These are:

• Volatile Wiper 0 • Volatile Wiper 1 • Volatile Wiper 2 • Volatile Wiper 3 • Terminal Control (TCON0) Register 0 • Terminal Control (TCON)1 Register 1

The volatile memory starts functioning at the RAMretention voltage (VRAM). The POR/BOR Wiper code isshown in Table 4-1.

TABLE 4-1: STANDARD SETTINGS

Resistance Code

Typical RAB Value

Default POR Wiper

Setting

Wiper Code

8-bit 7-bit

-502 5.0 k Mid scale 80h 40h-103 10.0 k Mid scale 80h 40h-503 50.0 k Mid scale 80h 40h-104 100.0 k Mid scale 80h 40h

TABLE 4-2: MEMORY MAP AND THE SUPPORTED COMMANDS

Address Function Memory Type Allowed Commands Disallowed Commands (1) Factory

Initialization

00h Volatile Wiper 0 RAM Read, Write, Increment, Decrement

— 7-bit 040h8-bit 080h

01h Volatile Wiper 1 RAM Read, Write, Increment, Decrement

— 7-bit 040h8-bit 080h

02h Reserved — None All —03h Reserved — None All —04h Volatile

TCON0 RegisterRAM Read, Write Increment, Decrement 1FFh

05h Reserved — None All —06h Volatile Wiper 2 RAM Read, Write,

Increment, Decrement— 7-bit 040h

8-bit 080h07h Volatile Wiper 3 RAM Read, Write,

Increment, Decrement— 7-bit 040h

8-bit 080h08h Reserved — None All —09h Reserved — None All —0Ah Volatile

TCON1 RegisterRAM Read, Write Increment, Decrement 1FFh

0Bh-0Fh Reserved — None All —Note 1: This command on this address will generate an error condition. To exit the error condition, the user must

take the CS pin to the VIH level and then back to the active state (VIL or VIHH).


MCP433X/435X4.2.1.1 Terminal Control (TCON) Registers There are two Terminal Control (TCON) Registers.These are called TCON0 and TCON1. Each registercontains 8 control bits. Four bits for each Wiper.Register 4-1 describes each bit of the TCON0 register,while Register 4-2 describes each bit of the TCON1register.

The state of each resistor network terminal connectionis individually controlled. That is, each terminalconnection (A, B and W) can be individually connected/

disconnected from the resistor network. This allows thesystem to minimize the currents through the digitalpotentiometer.

The value that is written to the specified TCON registerwill appear on the appropriate resistor networkterminals when the serial command has completed.

On a POR/BOR these registers are loaded with1FFh (9-bits), for all terminals connected. The hostcontroller needs to detect the POR/BOR event andthen update the volatile TCON register values.

REGISTER 4-1: TCON0 BITS (1)

R-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1D8 R1HW R1A R1W R1B R0HW R0A R0W R0B

bit 8 bit 0

Legend:R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown

bit 8 D8: Reserved. Forced to “1”bit 7 R1HW: Resistor 1 Hardware Configuration Control bit

This bit forces Resistor 1 into the “shutdown” configuration of the Hardware pin1 = Resistor 1 is NOT forced to the hardware pin “shutdown” configuration0 = Resistor 1 is forced to the hardware pin “shutdown” configuration

bit 6 R1A: Resistor 1 Terminal A (P1A pin) Connect Control bit This bit connects/disconnects the Resistor 1 Terminal A to the Resistor 1 Network1 = P1A pin is connected to the Resistor 1 Network0 = P1A pin is disconnected from the Resistor 1 Network

bit 5 R1W: Resistor 1 Wiper (P1W pin) Connect Control bitThis bit connects/disconnects the Resistor 1 Wiper to the Resistor 1 Network1 = P1W pin is connected to the Resistor 1 Network0 = P1W pin is disconnected from the Resistor 1 Network

bit 4 R1B: Resistor 1 Terminal B (P1B pin) Connect Control bitThis bit connects/disconnects the Resistor 1 Terminal B to the Resistor 1 Network1 = P1B pin is connected to the Resistor 1 Network0 = P1B pin is disconnected from the Resistor 1 Network

bit 3 R0HW: Resistor 0 Hardware Configuration Control bit This bit forces Resistor 0 into the “shutdown” configuration of the Hardware pin1 = Resistor 0 is NOT forced to the hardware pin “shutdown” configuration0 = Resistor 0 is forced to the hardware pin “shutdown” configuration

bit 2 R0A: Resistor 0 Terminal A (P0A pin) Connect Control bitThis bit connects/disconnects the Resistor 0 Terminal A to the Resistor 0 Network1 = P0A pin is connected to the Resistor 0 Network0 = P0A pin is disconnected from the Resistor 0 Network



Note 1: These bits do not affect the wiper register values.

MCP433X/435X


REGISTER 4-2: TCON1 BITS (1)

R-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1D8 R3HW R3A R3W R3B R2HW R2A R2W R2B

bit 8 bit 0

Legend:R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown

bit 8 D8: Reserved. Forced to “1”bit 7 R3HW: Resistor 3 Hardware Configuration Control bit

This bit forces Resistor 3 into the “shutdown” configuration of the Hardware pin1 = Resistor 3 is NOT forced to the hardware pin “shutdown” configuration0 = Resistor 3 is forced to the hardware pin “shutdown” configuration

bit 6 R3A: Resistor 3 Terminal A (P3A pin) Connect Control bit This bit connects/disconnects the Resistor 3 Terminal A to the Resistor 3 Network1 = P3A pin is connected to the Resistor 3 Network0 = P3A pin is disconnected from the Resistor 3 Network



bit 3 R2HW: Resistor 2 Hardware Configuration Control bit This bit forces Resistor 2 into the “shutdown” configuration of the Hardware pin1 = Resistor 2 is NOT forced to the hardware pin “shutdown” configuration0 = Resistor 2 is forced to the hardware pin “shutdown” configuration

bit 2 R2A: Resistor 2 Terminal A (P0A pin) Connect Control bitThis bit connects/disconnects the Resistor 2 Terminal A to the Resistor 2 Network1 = P2A pin is connected to the Resistor 2 Network0 = P2A pin is disconnected from the Resistor 2 Network



Note 1: These bits do not affect the wiper register values.


MCP433X/435X

5.0 RESISTOR NETWORKThe Resistor Network has either 7-bit or 8-bitresolution. Each Resistor Network allows zero scale tofull scale connections. Figure 5-1 shows a blockdiagram for the resistive network of a device.

The Resistor Network is made up of several parts.These include:

• Resistor Ladder• Wiper• Shutdown (Terminal Connections)

Devices have either four resistor networks. These arereferred to as Pot 0, Pot 1, Pot 2 and Pot 3.

FIGURE 5-1: Resistor Block Diagram.

5.1 Resistor Ladder ModuleThe resistor ladder is a series of equal value resistors(RS) with a connection point (tap) between the tworesistors. The total number of resistors in the series(ladder) determines the RAB resistance (seeFigure 5-1). The end points of the resistor ladder areconnected to analog switches which are connected tothe device terminal A and terminal B pins. The RAB(and RS) resistance has small variations over voltageand temperature.

For an 8-bit device, there are 256 resistors in a stringbetween terminal A and terminal B. The wiper can beset to tap onto any of these 256 resistors thus providing257 possible settings (including terminal A andterminal B).

For a 7-bit device, there are 128 resistors in a stringbetween terminal A and terminal B. The wiper can beset to tap onto any of these 128 resistors thus providing129 possible settings (including terminal A andterminal B).

Equation 5-1 shows the calculation for the stepresistance.

EQUATION 5-1: RS CALCULATION

RS

A

RS

RS

RS

B

257

256

255

1

0

RW (1)

W

(01h)

Analog Mux

RW (1) (00h)

RW (1) (FEh)

RW (1) (FFh)

RW (1) (100h)

Note 1: The wiper resistance is dependent onseveral factors including, wiper code,device VDD, Terminal voltages (on A, Band W), and temperature. Also for the same conditions, each tapselection resistance has a small variation.This RW variation has greater effects onsome specifications (such as INL) for thesmaller resistance devices (5.0 k)compared to larger resistance devices(100.0 k).

RAB

8-BitN =

128

127

126

1

0

(01h)

(00h)

(7Eh)

(7Fh)

(80h)

7-BitN =

RSRAB256 -------------=

RSRAB128 --------------=

8-bit Device

7-bit Device

MCP433X/435X


5.2 WiperEach tap point (between the RS resistors) is aconnection point for an analog switch. The oppositeside of the analog switch is connected to a commonsignal which is connected to the Terminal W (Wiper)pin.

A value in the volatile wiper register selects whichanalog switch to close, connecting the W terminal tothe selected node of the resistor ladder.

The wiper can connect directly to Terminal B or toTerminal A. A zero scale connection, connects theTerminal W (wiper) to Terminal B (wiper setting of000h). A full scale connection, connects the Terminal W(wiper) to Terminal A (wiper setting of 100h or 80h). Inthese configurations the only resistance between theTerminal W and the other Terminal (A or B) is that of theanalog switches.

A wiper setting value greater than full scale (wipersetting of 100h for 8-bit device or 80h for 7-bit devices)will also be a full scale setting (Terminal W (wiper) con-nected to Terminal A). Table 5-1 illustrates the full wipersetting map.

Equation 5-2 illustrates the calculation used todetermine the resistance between the wiper andterminal B.

EQUATION 5-2: RWB CALCULATION

RWBRABN256 -------------- RW+=

N = 0 to 256 (decimal)

RWBRABN128 -------------- RW+=

N = 0 to 128 (decimal)

8-bit Device

7-bit Device

TABLE 5-1: VOLATILE WIPER VALUE VS. WIPER POSITION MAP

Wiper SettingProperties

7-bit 8-bit

3FFh-081h

3FFh-101h

Reserved (Full Scale (W = A)),Increment and Decrement commands ignored

080h 100h Full Scale (W = A), Increment commands ignored

07Fh-041h

0FFh-081h

W = N

040h 080h W = N (Mid Scale)03Fh-001h

07Fh-001h

W = N

000h 000h Zero Scale (W = B)Decrement command ignored


MCP433X/435X5.3 Shutdown Shutdown is used to minimize the device’s currentconsumption. The MCP43XX has one method toachieve this:

• Terminal Control Register (TCON) This is different from the MCP42XXX devices in that theHardware Shutdown pin (SHDN) has been replaced bya RESET pin. The Hardware Shutdown pin function isstill available via software commands to the TCONregister.

5.3.1 TERMINAL CONTROL REGISTER (TCON)

The Terminal Control (TCON) register is a volatileregister used to configure the connection of eachresistor network terminal pin (A, B and W) to theResistor Network. These registers are shown inRegister 4-1 and Register 4-2.

The RxHW bit forces the selected resistor network intothe same state as the MCP42X1’s SHDN pin. Alternatelow-power configurations may be achieved with theRxA, RxW and RxB bits.

When the RxHW bit is “0”:

• The P0A, P1A, P2A and P3A terminals are disconnected

• The P0W, P1W, P2W and P3W terminals are simultaneously connect to the P0B, P1B, P2B and P3B terminals, respectively (see Figure 5-2)

The RxHW bit does NOT corrupt the values in theVolatile Wiper Registers nor the TCON register. Whenthe Shutdown mode is exited (RxHW bit = 1):

• The device returns to the Wiper setting specified by the Volatile Wiper value

• The TCON register bits return to controlling the terminal connection state

FIGURE 5-2: Resistor Network Shutdown State (RxHW = 0).

Note: When the RxHW bit forces the resistornetwork into the hardware SHDN state,the state of the TCON0 or TCON1register’s RxA, RxW and RxB bits isoverridden (ignored). When the state ofthe RxHW bit no longer forces the resistornetwork into the hardware SHDN state,the TCON0 or TCON1 register’s RxA,RxW and RxB bits return to controlling theterminal connection state. In other words,the RxHW bit does not corrupt the state ofthe RxA, RxW and RxB bits.

A

B

W

Res

isto

r Net

wor

k

MCP433X/435X


NOTES:


MCP433X/435X

6.0 SERIAL INTERFACE (SPI) The MCP43XX devices support the SPI serial protocol.This SPI operates in the Slave mode (does notgenerate the serial clock).

The SPI interface uses up to four pins. These are:

• CS – Chip Select • SCK – Serial Clock • SDI – Serial Data In • SDO – Serial Data Out

Typical SPI Interface is shown in Figure 6-1. In the SPIinterface, the Master’s Output pin is connected to theSlave’s Input pin and the Master’s Input pin isconnected to the Slave’s Output pin.

The MCP4XXX SPI’s module supports two (of the four)standard SPI modes. These are Mode 0,0 and 1,1. TheSPI mode is determined by the state of the SCK pin(VIH or VIL) on the when the CS pin transitions frominactive (VIH) to active (VIL or VIHH).

All SPI interface signals are high-voltage tolerant.

FIGURE 6-1: Typical SPI Interface Block Diagram.

SDISDO

MCP4XXX

SDOSDI

SCKSCK

(Master Out – Slave In (MOSI))

(Master In – Slave Out (MISO))

HostController

Typical SPI Interface Connections

CSI/O (1)

Note 1: If high voltage commands are desired, some type of external circuitry needs to be implemented.

MCP433X/435X


6.1 SDI, SDO, SCK, and CS OperationThe operation of the four SPI interface pins arediscussed in this section. These pins are:

• SDI (Serial Data In)• SDO (Serial Data Out)• SCK (Serial Clock)• CS (Chip Select)

The serial interface works on either 8-bit or 16-bitboundaries depending on the selected command. TheChip Select (CS) pin frames the SPI commands.

6.1.1 SERIAL DATA IN (SDI)The Serial Data In (SDI) signal is the data signal intothe device. The value on this pin is latched on the risingedge of the SCK signal.

6.1.2 SERIAL DATA OUT (SDO)The Serial Data Out (SDO) signal is the data signal outof the device. The value on this pin is driven on thefalling edge of the SCK signal.

Once the CS pin is forced to the active level (VIL orVIHH), the SDO pin will be driven. The state of the SDOpin is determined by the serial bit’s position in thecommand, the command selected, and if there is acommand error state (CMDERR).

6.1.3 SERIAL CLOCK (SCK) (SPI FREQUENCY OF OPERATION)

The SPI interface is specified to operate up to 10 MHz.The actual clock rate depends on the configuration ofthe system and the serial command used. Table 6-1shows the SCK frequency.

6.1.4 THE CS SIGNAL The Chip Select (CS) signal is used to select the deviceand frame a command sequence. To start a command,or sequence of commands, the CS signal musttransition from the inactive state (VIH) to an active state(VIL or VIHH).

After the CS signal has gone active, the SDO pin isdriven and the clock bit counter is reset.

If an error condition occurs for an SPI command, thenthe command byte’s Command Error (CMDERR) bit(on the SDO pin) will be driven low (VIL). To exit theerror condition, the user must take the CS pin to the VIHlevel.

When the CS pin returns to the inactive state (VIH) theSPI module resets (including the Address Pointer).While the CS pin is in the inactive state (VIH), the serialinterface is ignored. This allows the host controller tointerface to other SPI devices using the same SDI,SDO and SCK signals.

The CS pin has an internal pull-up resistor. The resistoris disabled when the voltage on the CS pin is at the VILlevel. This means that when the CS pin is not driven,the internal pull-up resistor will pull this signal to the VIHlevel. When the CS pin is driven low (VIL), theresistance becomes very large to reduce the devicecurrent consumption.

The high voltage capability of the CS pin allows HighVoltage commands. Support of High Voltagecommands allows circuit compatibility with thecorresponding nonvolatile device.

TABLE 6-1: SCK FREQUENCY (1)

Memory Type Access

Command

ReadWrite,

Increment, Decrement

Volatile Memory

SDI, SDO 10 MHz 10 MHz

Note 1: This is the maximum clock frequency without an external pull-up resistor.

Note: There is a required delay after the CS pingoes active to the 1st edge of the SCK pin.


MCP433X/435X6.2 The SPI ModesThe SPI module supports two (of the four) standard SPImodes. These are Mode 0,0 and 1,1. The mode isdetermined by the state of the SDI pin on the risingedge of the 1st clock bit (of the 8-bit byte).

6.2.1 MODE 0,0 In Mode 0,0: SCK Idle state = low (VIL), data is clockedin on the SDI pin on the rising edge of SCK and clockedout on the SDO pin on the falling edge of SCK.

6.2.2 MODE 1,1 In Mode 1,1: SCK Idle state = high (VIH), data isclocked in on the SDI pin on the rising edge of SCK andclocked out on the SDO pin on the falling edge of SCK.

6.3 SPI WaveformsFigure 6-2 through Figure 6-5 show the different SPIcommand waveforms. Figure 6-2 and Figure 6-3 areread and write commands. Figure 6-4 and Figure 6-5are Increment and Decrement commands. Support ofHigh Voltage commands allows circuit compatibilitywith the corresponding nonvolatile device.

FIGURE 6-2: 16-Bit Commands (Write, Read) – SPI Waveform (Mode 1,1).

FIGURE 6-3: 16-Bit Commands (Write, Read) – SPI Waveform (Mode 0,0).

CS

SCK

Write toSSPBUF

SDI

InputSample

SDO bit15 bit14 bit13 bit12 bit11 bit10 bit9 bit8 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0

bit15 bit14 bit13 bit12 bit9 bit8 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0AD3 AD2 AD1 AD0

C1 C0X D8 D7 D6 D5 D4 D3 D2 D1 D0

VIH

VIL

CMDERR bit

VIHH

CS

SCK

Write toSSPBUF

SDI

InputSample

SDO bit15 bit14 bit13 bit12 bit11 bit10 bit9 bit8 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0

bit15 bit14 bit13 bit12 bit9 bit8 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0AD3 AD2 AD1 AD0

C1 C0X D8 D7 D6 D5 D4 D3 D2 D1 D0

VIH

VIL

CMDERR bit

VIHH

MCP433X/435X


FIGURE 6-4: 8-Bit Commands (Increment, Decrement) – SPI Waveform with PIC MCU (Mode 1,1).

FIGURE 6-5: 8-Bit Commands (Increment, Decrement) – SPI Waveform with PIC MCU (Mode 0,0).

bit7 bit0

bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0

CS

SCK

Write toSSPBUF

SDI

InputSample

SDO

VIH

VIL

AD3 AD2 AD1 AD0 C0 C1 X X

“1” = Valid Command“0” = Invalid Command

CMDERR bit

VIHH

SCK

InputSample

SDI

bit7 bit0

SDO bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0

Write toSSPBUF

CS

VIH

VIL

AD3 AD2 AD1 AD0 C0 C1 X X

“1” = Valid Command“0” = Invalid Command

CMDERR bit

VIHH


MCP433X/435X

7.0 DEVICE COMMANDSThe MCP43XX’s SPI command format supports16 memory address locations and four commands.Each command has two modes:

• Normal Serial Commands• High-Voltage Serial Commands

Normal serial commands are those where the CS pin isdriven to VIL. With high-voltage serial commands, theCS pin is driven to VIHH. In each mode, there are fourpossible commands. These commands are shown inTable 7-1.

The 8-bit commands (Increment Wiper andDecrement Wiper commands) contain a commandbyte, see Figure 7-1, while 16-bit commands (ReadData and Write Data commands) contain a commandbyte and a data byte. The command byte contains twodata bits, see Figure 7-1.

Table 7-2 shows the supported commands for eachmemory location and the corresponding values on theSDI and SDO pins.

Table 7-3 shows an overview of all the SPI commandsand their interaction with other device features.

7.1 Command ByteThe command byte has three fields, the address, thecommand, and 2 data bits, see Figure 7-1. Currentlyonly one of the data bits is defined (D8). This is for theWrite command.

The device memory is accessed when the mastersends a proper command byte to select the desiredoperation. The memory location getting accessed iscontained in the command byte’s AD3:AD0 bits. Theaction desired is contained in the command byte’sC1:C0 bits, see Table 7-1. C1:C0 determines if thedesired memory location will be read, written,incremented (wiper setting +1) or decremented (wipersetting -1). The Increment and Decrement commandsare only valid on the volatile wiper registers.

As the command byte is being loaded into the device(on the SDI pin), the device’s SDO pin is driving. TheSDO pin will output high bits for the first six bits of thatcommand. On the 7th bit, the SDO pin will output theCMDERR bit state (see Section 7.3 “ErrorCondition”). The 8th bit state depends on thecommand selected.

FIGURE 7-1: General SPI Command Formats.

TABLE 7-1: COMMAND BIT OVERVIEW

C1:C0 Bit

StatesCommand # of

Bits

Operates on Volatile/ Nonvolatile memory

11 Read Data 16-Bits Both00 Write Data 16-Bits Both01 Increment 8-Bits Volatile Only10 Decrement 8-Bits Volatile Only

AD3

AD2

AD1

AD0

C1

C0

D9

D8

Memory

Command Byte

Data Address Bits

CommandBits

AD3

AD2

AD1

AD0

C1

C0

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Memory

16-bit Command

Data Address Bits

CommandBits

0 0 = Write Data0 1 = INCR1 0 = DECR1 1 = Read Data

C C1 0

CommandBits

8-bit Command

Command Byte Data Byte

MCP433X/435X


TABLE 7-2: MEMORY MAP AND THE SUPPORTED COMMANDSAddress

Command Data(10-bits) (1)

SPI String (Binary) Value Function MOSI (SDI pin) MISO (SDO pin) (2) 00h Volatile Wiper 0 Write Data nn nnnn nnnn 0000 00nn nnnn nnnn 1111 1111 1111 1111

Read Data nn nnnn nnnn 0000 11nn nnnn nnnn 1111 111n nnnn nnnnIncrement Wiper — 0000 0100 1111 1111Decrement Wiper — 0000 1000 1111 1111

01h Volatile Wiper 1 Write Data nn nnnn nnnn 0001 00nn nnnn nnnn 1111 1111 1111 1111Read Data nn nnnn nnnn 0001 11nn nnnn nnnn 1111 111n nnnn nnnnIncrement Wiper — 0001 0100 1111 1111Decrement Wiper — 0001 1000 1111 1111

02h Reserved None — — —03h Reserved None — — —

04h (3) Volatile TCON 0 Register

Write Data nn nnnn nnnn 0100 00nn nnnn nnnn 1111 1111 1111 1111Read Data nn nnnn nnnn 0100 11nn nnnn nnnn 1111 111n nnnn nnnn

05h Reserved None — — —06h Volatile Wiper 2 Write Data nn nnnn nnnn 0110 00nn nnnn nnnn 1111 1111 1111 1111

Read Data nn nnnn nnnn 0110 11nn nnnn nnnn 1111 111n nnnn nnnnIncrement Wiper — 0110 0100 1111 1111Decrement Wiper — 0110 1000 1111 1111

07h Volatile Wiper 3 Write Data nn nnnn nnnn 0111 00nn nnnn nnnn 1111 1111 1111 1111Read Data nn nnnn nnnn 0111 11nn nnnn nnnn 1111 111n nnnn nnnnIncrement Wiper — 0111 0100 1111 1111Decrement Wiper — 0111 1000 1111 1111

08h Reserved None — — —09h Reserved None — — —

0Ah (3) Volatile TCON 1 Register

Write Data nn nnnn nnnn 1010 00nn nnnn nnnn 1111 1111 1111 1111Read Data nn nnnn nnnn 1010 11nn nnnn nnnn 1111 111n nnnn nnnn

0Bh-0Fh Reserved None — — —Note 1: The data memory is only 9-bits wide, so the MSb is ignored by the device.

2: All these address/command combinations are valid, so the CMDERR bit is set. Any other address/command combina-tion is a command error state and the CMDERR bit will be clear.

3: Increment or Decrement commands are invalid for these addresses.


MCP433X/435X7.2 Data ByteOnly the Read command and the Write command usethe data byte, see Figure 7-1. These commandsconcatenate the 8 bits of the data byte with the onedata bit (D8) contained in the command byte to form9-bits of data (D8:D0). The command byte formatsupports up to 9-bits of data so that the 8-bit resistornetwork can be set to full scale (100h or greater). Thisallows wiper connections to Terminal A and toTerminal B.

The D9 bit is currently unused, and corresponds to theposition on the SDO data of the CMDERR bit.

7.3 Error ConditionThe CMDERR bit indicates if the four address bitsreceived (AD3:AD0) and the two command bitsreceived (C1:C0) are a valid combination (seeTable 4-2). The CMDERR bit is high if the combinationis valid and low if the combination is invalid.

The command error bit will also be low if a write to anonvolatile address has been specified and anotherSPI command occurs before the CS pin is driveninactive (VIH).

SPI commands that do not have a multiple of 8 clocksare ignored.

Once an error condition has occurred, any followingcommands are ignored. All following SDO bits will below until the CMDERR condition is cleared by forcingthe CS pin to the inactive state (VIH).

7.3.1 ABORTING A TRANSMISSIONAll SPI transmissions must have the correct number ofSCK pulses to be executed. The command is notexecuted until the complete number of clocks havebeen received. Some commands also require the CSpin to be forced inactive (VIH). If the CS pin is forced tothe inactive state (VIH) the serial interface is reset.Partial commands are not executed.

SPI is more susceptible to noise than other busprotocols. The most likely case is that this noisecorrupts the value of the data being clocked into theMCP43XX or the SCK pin is injected with extra clockpulses. This may cause data to be corrupted in thedevice, or a command error to occur, since the addressand command bits were not a valid combination. Theextra SCK pulse will also cause the SPI data (SDI) andclock (SCK) to be out of sync. Forcing the CS pin to theinactive state (VIH) resets the serial interface. The SPIinterface will ignore activity on the SDI and SCK pinsuntil the CS pin transition to the active state is detected(VIH to VIL or VIH to VIHH).

Note 1: When data is not being received by theMCP43XX, It is recommended that theCS pin be forced to the inactive level (VIL)

2: It is also recommended that longcontinuous command strings should bebroken down into single commands orshorter continuous command strings.This reduces the probability of noise onthe SCK pin corrupting the desired SPIcommands.

MCP433X/435X


7.4 Continuous Commands The device supports the ability to execute commandscontinuously. While the CS pin is in the active state (VILor VIHH). Any sequence of valid commands may bereceived.

The following example is a valid sequence of events:

1. CS pin driven active (VIL or VIHH).2. Read Command.3. Increment Command (Wiper 0).4. Increment Command (Wiper 0).5. Decrement Command (Wiper 1).6. Write Command (volatile memory).7. CS pin driven inactive (VIH).

Note 1: It is recommended that while the CS pin isactive, only one type of command shouldbe issued. When changing commands, itis recommended to take the CS pininactive then force it back to the activestate.

2: It is also recommended that longcommand strings should be broken downinto shorter command strings. Thisreduces the probability of noise on theSCK pin corrupting the desired SPIcommand string.

TABLE 7-3: COMMANDS

Command Name # of Bits

High Voltage

(VIHH) on CS pin?

Write Data 16-Bits —Read Data 16-Bits —Increment Wiper 8-Bits —Decrement Wiper 8-Bits —High-Voltage Write Data 16-Bits YesHigh-Voltage Read Data 16-Bits YesHigh-Voltage Increment Wiper 8-Bits YesHigh-Voltage Decrement Wiper 8-Bits Yes


MCP433X/435X7.5 Write Data

Normal and High VoltageThe Write command is a 16-bit command. The formatof the command is shown in Figure 7-2.

A Write command to a volatile memory locationchanges that location after a properly formatted Writecommand (16-clock) have been received.

7.5.1 SINGLE WRITE TO VOLATILE MEMORY

The write operation requires that the CS pin be in theactive state (VILor VIHH). Typically, the CS pin will be inthe inactive state (VIH) and is driven to the active state(VIL). The 16-bit Write command (command byte anddata byte) is then clocked in on the SCK and SDI pins.Once all 16 bits have been received, the specifiedvolatile address is updated. A write will not occur if thewrite command isn’t exactly 16 clocks pulses. Thisprotects against system issues from corrupting thenonvolatile memory locations.

Figure 6-2 and Figure 6-3 show possible waveformsfor a single write.

FIGURE 7-2: Write Command – SDI and SDO States.

AD3

AD2

AD1

AD0

0 0 D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Valid Address/Command combination1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 Invalid Address/Command combination (1)

COMMAND BYTE DATA BYTE

SDI

SDO

Note 1: If an Error Condition occurs (CMDERR = L), all following SDO bits will be low until the CMDERRcondition is cleared (the CS pin is forced to the inactive state).

MCP433X/435X


7.5.2 CONTINUOUS WRITES TO VOLATILE MEMORY

Continuous writes are possible only when writing to thevolatile memory registers (address 00h, 01h and 04h).

Figure 7-3 shows the sequence for three continuouswrites. The writes do not need to be to the same volatilememory address.

FIGURE 7-3: Continuous Write Sequence.

AD3

AD2

AD1

AD0

0 0 D9 D8

D7

D6

D5

D4

D3

D2

D1

D0

1 1 1 1 1 1 1* 1 1 1 1 1 1 1 1 1

AD3

AD2

AD1

AD0

0 0 D9 D8

D7

D6

D5

D4

D3

D2

D1

D0

1 1 1 1 1 1 1* 1 1 1 1 1 1 1 1 1

AD3

AD2

AD1

AD0

0 0 D9 D8

D7

D6

D5

D4

D3

D2

D1

D0

1 1 1 1 1 1 1* 1 1 1 1 1 1 1 1 1


SDI

SDO

Note 1: If a Command Error (CMDERR) occurs at this bit location (*), then all following SDO bits will bedriven low until the CS pin is driven inactive (VIH).


MCP433X/435X7.6 Read Data

Normal and High VoltageThe Read command is a 16-bit command. The formatof the command is shown in Figure 7-4.

The first 6 bits of the Read command determine theaddress and the command. The 7th clock will outputthe CMDERR bit on the SDO pin. The remaining9-clocks the device will transmit the 9 data bits (D8:D0)of the specified address (AD3:AD0).

Figure 7-4 shows the SDI and SDO information for aRead command.

7.6.1 SINGLE READThe read operation requires that the CS pin be in theactive state (VILor VIHH). Typically, the CS pin will be inthe inactive state (VIH) and is driven to the active state(VILor VIHH). The 16-bit Read command (commandbyte and data byte) is then clocked in on the SCK andSDI pins. The SDO pin starts driving data on the 7th bit(CMDERR bit) and the addressed data comes out onthe 8th through 16th clocks. Figure 6-2 throughFigure 6-3 show possible waveforms for a single read.

FIGURE 7-4: Read Command – SDI and SDO States.

AD3

AD2

AD1

AD0

1 1 X X X X X X X X X X

1 1 1 1 1 1 1 D8

D7

D6

D5

D4

D3

D2

D1

D0

Valid Address/Command combination

1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 Attempted Memory Read of Reserved Memory location


SDI

SDO

READ DATA

MCP433X/435X


7.6.2 CONTINUOUS READS Continuous reads allow the devices memory to be readquickly. Continuous reads are possible to all memorylocations.

Figure 7-5 shows the sequence for three continuousreads. The reads do not need to be to the samememory address.

FIGURE 7-5: Continuous Read Sequence.

AD3

AD2

AD1

AD0


1 1 1 1 1 1 1* D8

D7

D6

D5

D4

D3

D2

D1

D0

AD3

AD2

AD1

AD0


1 1 1 1 1 1 1* D8

D7

D6

D5

D4

D3

D2

D1

D0

AD3

AD2

AD1

AD0


1 1 1 1 1 1 1* D8

D7

D6

D5

D4

D3

D2

D1

D0


SDI

SDO

Note 1: If a Command Error (CMDERR) occurs at this bit location (*), then all following SDO bits will bedriven low until the CS pin is driven inactive (VIH).


MCP433X/435X7.7 Increment Wiper

Normal and High VoltageThe Increment command is an 8-bit command. TheIncrement command can only be issued to volatilememory locations. The format of the command isshown in Figure 7-6.

An Increment command to the volatile memory locationchanges that location after a properly formatted com-mand (8-clocks) have been received.

Increment commands provide a quick and easymethod to modify the value of the volatile wiper locationby +1 with minimal overhead.

FIGURE 7-6: Increment Command – SDI and SDO States.

7.7.1 SINGLE INCREMENT Typically, the CS pin starts at the inactive state (VIH),but may already be in the active state due to thecompletion of another command.

Figure 6-4 through Figure 6-5 show possiblewaveforms for a single increment. The incrementoperation requires that the CS pin be in the active state(VILor VIHH). Typically, the CS pin will be in the inactivestate (VIH) and is driven to the active state (VILor VIHH).The 8-bit Increment command (command byte) is thenclocked in on the SDI pin by the SCK pins. The SDO pindrives the CMDERR bit on the 7th clock.

The wiper value will increment up to 100h on 8-bitdevices and 80h on 7-bit devices. After the wiper valuehas reached full scale (8-bit = 100h, 7-bit = 80h), thewiper value will not be incremented further. If the wiperregister has a value between 101h and 1FFh, theIncrement command is disabled. See Table 7-4 foradditional information on the Increment commandversus the current volatile wiper value.

The increment operations only require the Incrementcommand byte while the CS pin is active (VILor VIHH)for a single increment.

After the wiper is incremented to the desired position,the CS pin should be forced to VIH to ensure thatunexpected transitions on the SCK pin do not causethe wiper setting to change. Driving the CS pin to VIHshould occur as soon as possible (within devicespecifications) after the last desired increment occurs.

Note: Table 7-2 shows the valid addresses forthe Increment Wiper command. Otheraddresses are invalid.

AD3

AD2

AD1

AD0

0 1 X X

1 1 1 1 1 1 1* 1 Note 1, 2 1 1 1 1 1 1 0 0 Note 1, 3

(INCR COMMAND (n+1))

SDI

SDO

COMMAND BYTE

Note 1: Only functions when writing the volatilewiper registers (AD3:AD0) 0h and 1h.

2: Valid Address/Command combination.

3: Invalid Address/Command combinationall following SDO bits will be low until theCMDERR condition is cleared. (the CSpin is forced to the inactive state).

4: If a Command Error (CMDERR) occursat this bit location (*), then all followingSDO bits will be driven low until the CSpin is driven inactive (VIH).

TABLE 7-4: INCREMENT OPERATION VS. VOLATILE WIPER VALUE

Current Wiper Setting Wiper (W)

Properties

Increment Command Operates?7-bit

Pot 8-bit Pot

3FFh081h

3FFh101h

Reserved (Full Scale (W = A))

No

080h 100h Full Scale (W = A) No07Fh041h

0FFh081

W = N

040h 080h W = N (Mid-scale) Yes03Fh001h

07Fh001

W = N

000h 000h Zero Scale (W = B) Yes

MCP433X/435X


7.7.2 CONTINUOUS INCREMENTS Continuous increments are possible only when writingto the volatile memory registers (address 00h, 01h, 06hand 07h).

Figure 7-7 shows a continuous increment sequence forthree continuous writes. The writes do not need to beto the same volatile memory address.

When executing an continuous Increment commands,the selected wiper will be altered from n to n+1 for eachIncrement command received. The wiper value willincrement up to 100h on 8-bit devices and 80h on 7-bitdevices. After the wiper value has reached full scale(8-bit = 100h, 7-bit = 80h), the wiper value will not beincremented further. If the wiper register has a valuebetween 101h and 1FFh, the Increment command isdisabled.

Increment commands can be sent repeatedly withoutraising CS until a desired condition is met.

When executing a continuous command string, theIncrement command can be followed by any other validcommand.

The wiper terminal will move after the command hasbeen received (8th clock).

After the wiper is incremented to the desired position,the CS pin should be forced to VIH to ensure thatunexpected transitions (on the SCK pin do not causethe wiper setting to change). Driving the CS pin to VIHshould occur as soon as possible (within devicespecifications) after the last desired increment occurs.

FIGURE 7-7: Continuous Increment Command – SDI and SDO States.

AD3

AD2

AD1

AD0

0 1 X X AD3

AD2

AD1

AD0

0 1 X X AD3

AD2

AD1

AD0

0 1 X X

1 1 1 1 1 1 1* 1 1 1 1 1 1 1 1* 1 1 1 1 1 1 1 1* 1 Note 1, 2 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Note 3, 4 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 Note 3, 4 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 Note 3, 4

(INCR COMMAND (n+1)) (INCR COMMAND (n+2)) (INCR COMMAND (n+3))

SDI

SDO

COMMAND BYTE COMMAND BYTE COMMAND BYTE

Note 1: Only functions when writing the volatile wiper registers (AD3:AD0) 0h and 1h.


3: Invalid Address/Command combination.

4: If an Error Condition occurs (CMDERR = L), all following SDO bits will be low until the CMDERRcondition is cleared (the CS pin is forced to the inactive state).


MCP433X/435X7.8 Decrement Wiper

Normal and High VoltageThe Decrement command is an 8-bit command. TheDecrement command can only be issued to volatilememory locations. The format of the command isshown in Figure 7-6.

A Decrement command to the volatile memory locationchanges that location after a properly formattedcommand (8 clocks) have been received.

Decrement commands provide a quick and easymethod to modify the value of the volatile wiper locationby -1 with minimal overhead.

FIGURE 7-8: Decrement Command – SDI and SDO States.

7.8.1 SINGLE DECREMENT Typically, the CS pin starts at the inactive state (VIH),but may already be in the active state due to thecompletion of another command.

Figure 6-4 through Figure 6-5 show possiblewaveforms for a single decrement. The decrementoperation requires that the CS pin be in the active state(VILor VIHH). Typically, the CS pin will be in the inactivestate (VIH) and is driven to the active state (VILor VIHH).Then the 8-bit Decrement command (command byte) isclocked in on the SDI pin by the SCK pins. The SDO pindrives the CMDERR bit on the 7th clock.

The wiper value will decrement from the wiper’s fullscale value (100h on 8-bit devices and 80h on 7-bitdevices). Above the wiper’s full scale value (8-bit =101h to 1FFh, 7-bit = 81h to FFh), the Decrement com-mand is disabled. If the wiper register has a zero scalevalue (000h), then the wiper value will not decrement.See Table 7-5 for additional information on the Decre-ment command vs. the current volatile wiper value.

The Decrement commands only require the Decrementcommand byte, while the CS pin is active (VILor VIHH)for a single decrement.

After the wiper is decremented to the desired position,the CS pin should be forced to VIH to ensure thatunexpected transitions on the SCK pin do not causethe wiper setting to change. Driving the CS pin to VIHshould occur as soon as possible (within devicespecifications) after the last desired decrement occurs.

Note: Table 7-2 shows the valid addresses forthe Decrement Wiper command. Otheraddresses are invalid.

AD3

AD2

AD1

AD0

1 0 X X

1 1 1 1 1 1 1* 1 Note 1, 2 1 1 1 1 1 1 0 0 Note 1, 3

(DECR COMMAND (n+1))

SDI

SDO

COMMAND BYTE

Note 1: Only functions when writing the volatilewiper registers (AD3:AD0) 0h and 1h.


3: Invalid Address/Command combinationall following SDO bits will be low until theCMDERR condition is cleared.(the CS pin is forced to the inactivestate).

4: If a Command Error (CMDERR) occursat this bit location (*), then all followingSDO bits will be driven low until the CSpin is driven inactive (VIH).

TABLE 7-5: DECREMENT OPERATION VS. VOLATILE WIPER VALUE

Current Wiper Setting Wiper (W)

Properties

Decrement Command Operates?7-bit

Pot 8-bit Pot

3FFh081h

3FFh101h

Reserved (Full Scale (W = A))

No

080h 100h Full Scale (W = A) Yes07Fh041h

0FFh081

W = N

040h 080h W = N (Mid-scale) Yes03Fh001h

07Fh001

W = N

000h 000h Zero Scale (W = B) No

MCP433X/435X


7.8.2 CONTINUOUS DECREMENTS Continuous decrements are possible only when writingto the volatile memory registers (address 00h, 01h, and04h).

Figure 7-9 shows a continuous decrement sequencefor three continuous writes. The writes do not need tobe to the same volatile memory address.

When executing continuous Decrement commands,the selected wiper will be altered from n to n-1 for eachDecrement command received. The wiper value willdecrement from the wiper’s full scale value (100h on8-bit devices and 80h on 7-bit devices). Above thewiper’s full scale value (8-bit = 101h to 1FFh,7-bit = 81h to FFh), the Decrement command isdisabled. If the Wiper register has a zero scale value(000h), then the wiper value will not decrement. SeeTable 7-5 for additional information on the Decrementcommand vs. the current volatile wiper value.

Decrement commands can be sent repeatedly withoutraising CS until a desired condition is met.

When executing a continuous command string, theDecrement command can be followed by any othervalid command.

The wiper terminal will move after the command hasbeen received (8th clock).

After the wiper is decremented to the desired position,the CS pin should be forced to VIH to ensure that“unexpected” transitions (on the SCK pin do not causethe wiper setting to change). Driving the CS pin to VIHshould occur as soon as possible (within devicespecifications) after the last desired decrement occurs.

FIGURE 7-9: Continuous Decrement Command – SDI and SDO States.

AD3

AD2

AD1

AD0

1 0 X X AD3

AD2

AD1

AD0

1 0 X X AD3

AD2

AD1

AD0

1 0 X X

1 1 1 1 1 1 1* 1 1 1 1 1 1 1 1* 1 1 1 1 1 1 1 1* 1 Note 1, 2 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Note 3, 4 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 Note 3, 4 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 Note 3, 4

(DECR COMMAND (n-1)) (DECR COMMAND (n-1)) (DECR COMMAND (n-1))

SDI

SDO

COMMAND BYTE COMMAND BYTE COMMAND BYTE

Note 1: Only functions when writing the volatile wiper registers (AD3:AD0) 0h and 1h.


3: Invalid Address/Command combination.

4: If an Error Condition occurs (CMDERR = L), all following SDO bits will be low until the CMDERRcondition is cleared (the CS pin is forced to the inactive state).


MCP433X/435X

8.0 APPLICATIONS EXAMPLESDigital potentiometers have a multitude of practicaluses in modern electronic circuits. The most popularuses include precision calibration of set point thresh-olds, sensor trimming, LCD bias trimming, audio atten-uation, adjustable power supplies, motor controlovercurrent trip setting, adjustable gain amplifiers andoffset trimming. The MCP433X/435X devices can beused to replace the common mechanical trim pot inapplications where the operating and terminal voltagesare within CMOS process limitations (VDD = 2.7V to5.5V).

8.1 Split Rail ApplicationsAll inputs that would be used to interface to a hostcontroller support high voltage on their input pin. Thisallows the MCP43XX device to be used in split powerrail applications.

An example of this is a battery application where thePIC® MCU is directly powered by the battery supply(4.8V) and the MCP43XX device is powered by the3.3V regulated voltage.

For SPI applications, these inputs are:

• CS • SCK • SDI (or SDI/SDO)• RESET

Figure 8-1 through Figure 8-2 show three example splitrail systems. In this system, the MCP43XX interfaceinput signals need to be able to support the PIC MCUoutput high voltage (VOH).

In Example #1 (Figure 8-1), the MCP43XX interfaceinput signals need to be able to support the PIC MCUoutput high voltage (VOH). If the split rail voltage deltabecomes too large, then the customer may be requiredto do some level shifting due to MCP43XX VOH levelsrelated to host controller VIH levels.

In Example #2 (Figure 8-2), the MCP43XX interfaceinput signals need to be able to support the lowervoltage of the PIC MCU output high voltage level (VOH).

Table 8-1 shows an example PIC microcontroller I/Ovoltage specifications and the MCP43XXspecifications. So this PIC MCU operating at 3.3V willdrive a VOH at 2.64V, and for the MCP43XX operatingat 5.5V, the VIH is 2.47V. Therefore, the interfacesignals meet specifications.

FIGURE 8-1: Example Split Rail System 1.

FIGURE 8-2: Example Split Rail System 2.

TABLE 8-1: VOH – VIH COMPARISONS PIC® MCU (1) MCP4XXX (2)

CommentVDD VIH VOH VDD VIH VOH

5.5 4.4 4.4 2.7 1.215 — (3) 5.0 4.0 4.0 3.0 1.35 — (3) 4.5 3.6 3.6 3.3 1.485 — (3) 3.3 2.64 2.64 4.5 2.025 — (3) 3.0 2.4 2.4 5.0 2.25 — (3) 2.7 2.16 2.16 5.5 2.475 — (3) Note 1: VOH minimum = 0.8 * VDD;

VOL maximum = 0.6V VIH minimum = 0.8 * VDD; VIL maximum = 0.2 * VDD;

2: VOH minimum (SDA only) =; VOL maximum = 0.2 * VDD VIH minimum = 0.45 * VDD; VIL maximum = 0.2 * VDD

3: The only MCP4XXX output pin is SDO, which is open-drain (or open-drain with internal pull-up) with high voltage support

VoltageRegulator

5V 3V

PIC® MCU MCP4XXX

SDICS SCK

RESET

SDICS

SCK

I/OSDOSDO

VoltageRegulator3V

5V

PIC® MCU MCP4XXX

SDICS SCK

RESET

SDICS

SCK

I/OSDOSDO

MCP433X/435X


8.2 Techniques to Force the CS Pin to VIHH

The circuit in Figure 8-3 shows a method using theTC1240A doubling charge pump. When the SHDN pinis high, the TC1240A is off, and the level on the CS pinis controlled by the PIC® microcontrollers (MCUs) IO2pin.

When the SHDN pin is low, the TC1240A is on and theVOUT voltage is 2 * VDD. The resistor R1 allows the CSpin to go higher than the voltage such that the PICMCU’s IO2 pin “clamps” at approximately VDD.

FIGURE 8-3: Using the TC1240A to Generate the VIHH Voltage.The circuit in Figure 8-4 shows the method used on theMCP402X Nonvolatile Digital Potentiometer EvaluationBoard (Part Number: MCP402XEV). This methodrequires that the system voltage be approximately 5V.This ensures that when the PIC10F206 enters abrown-out condition, there is an insufficient voltagelevel on the CS pin to change the stored value of thewiper. The “MCP402X Nonvolatile DigitalPotentiometer Evaluation Board User’s Guide”(DS51546) contains a complete schematic.

GP0 is a general purpose I/O pin, while GP2 can eitherbe a general purpose I/O pin or it can output the internalclock.

For the serial commands, configure the GP2 pin as aninput (high-impedance). The output state of the GP0pin will determine the voltage on the CS pin (VIL or VIH).

For high-voltage serial commands, force the GP0output pin to output a high level (VOH) and configure theGP2 pin to output the internal clock. This will form acharge pump and increase the voltage on the CS pin(when the system voltage is approximately 5V).

FIGURE 8-4: MCP4XXX Nonvolatile Digital Potentiometer Evaluation Board (MCP402XEV) implementation to generate the VIHH voltage.

8.3 Using Shutdown ModesFigure 8-5 shows a possible application circuit wherethe independent terminals could be used.Disconnecting the wiper allows the transistor input tobe taken to the bias voltage level (disconnecting A andor B may be desired to reduce system current).Disconnecting Terminal A modifies the transistor inputby the RBW rheostat value to the Common B.Disconnecting Terminal B modifies the transistor inputby the RAW rheostat value to the Common A. TheCommon A and Common B connections could beconnected to VDD and VSS.

FIGURE 8-5: Example Application Circuit using Terminal Disconnects.

CS

PIC® MCU

MCP4XXX R1

IO1

IO2 C2

TC1240A VIN SHDN

C+C-

VOUT

C1

CS

PIC10F206

MCP4XXX

R1 GP0

GP2

C2 C1

Balance Bias

W

BInput

Input

To baseof Transistor(or Amplifier)

A

Common B

Common A


MCP433X/435X8.4 Design ConsiderationsIn the design of a system with the MCP43XX devices,the following considerations should be taken intoaccount:

• Power Supply Considerations• Layout Considerations

8.4.1 POWER SUPPLY CONSIDERATIONS

The typical application will require a bypass capacitorin order to filter high-frequency noise, which can beinduced onto the power supply’s traces. The bypasscapacitor helps to minimize the effect of these noisesources on signal integrity. Figure 8-6 illustrates anappropriate bypass strategy.

In this example, the recommended bypass capacitorvalue is 0.1 µF. This capacitor should be placed asclose (within 4 mm) to the device power pin (VDD) aspossible.

The power source supplying these devices should beas clean as possible. If the application circuit hasseparate digital and analog power supplies, VDD andVSS should reside on the analog plane.

FIGURE 8-6: Typical Microcontroller Connections.

8.4.2 LAYOUT CONSIDERATIONSSeveral layout considerations may be applicable toyour application. These may include:

• Noise• Footprint Compatibility• PCB Area Requirements

8.4.2.1 NoiseInductively-coupled AC transients and digital switchingnoise can degrade the input and output signal integrity,potentially masking the MCP43XX’s performance.Careful board layout minimizes these effects andincreases the Signal-to-Noise Ratio (SNR). Multi-layerboards utilizing a low-inductance ground plane,isolated inputs, isolated outputs and proper decouplingare critical to achieving the performance that thesilicon is capable of providing. Particularly harshenvironments may require shielding of critical signals.

If low noise is desired, breadboards and wire-wrappedboards are not recommended.

8.4.2.2 Footprint CompatibilityThe specification of the MCP43XX pinouts was done toallow systems to be designed to easily support the useof either the dual (MCP42XX) or quad (MCP43XX)device.

Figure 8-7 shows how the dual pinout devices fit on thequad device footprint. For the Rheostat devices, thedual device is in the MSOP package, so the footprintswould need to be offset from each other.

FIGURE 8-7: Quad Pinout (TSSOP Package) vs. Dual Pinout.

VDD

VDD

VSS VSS

MC

P433

X/43

5X

0.1 µF

PIC

® M

icro

cont

rolle

r

0.1 µF

U/D

CS

W

B

A

1234 17

181920

RESETSDO

WP

VDD

MCP43X1 Quad Potentiometers

TSSOP

567 14

1516

P0WP0B

P0AP1AP1WP1BVSS

CS

SDISCK

MCP43X2 Quad Rheostat

1234 11

121314

P0BSDO

P0W

VDD

TSSOP

567 8

910

P2W

P1W

P2BP3BP3W

P1BVSS

CS

SDISCK

8910

P3BP3WP3A

1212

P2WP2A

P2B

11

MCP42X1 Pinout (1)

MCP42X2 Pinout

Note 1: Pin 15 (RESET) is the Shutdown(SHDN) pin on the MCP42x1 device.

MCP433X/435X


Figure 8-8 shows possible layout implementations foran application to support the quad and dual options onthe same PCB.

FIGURE 8-8: Layout to support Quad and Dual Devices.

8.4.2.3 PCB Area RequirementsIn some applications, PCB area is a criteria for deviceselection. Table 8-2 shows the package dimensionsand area for the different package options. The tablealso shows the relative area factor compared to thesmallest area. For space critical applications, the QFNpackage would be the suggested package.

8.4.3 RESISTOR TEMPCO Characterization curves of the resistor temperaturecoefficient (Tempco) are shown in Figure 2-11,Figure 2-32, Figure 2-52, and Figure 2-72.

These curves show that the resistor network isdesigned to correct for the change in resistance astemperature increases. This technique reduces theend to end change is RAB resistance.

8.4.4 HIGH VOLTAGE TOLERANT PINSHigh voltage support (VIHH) on the Serial Interface pinssupports in-circuit accommodation of split railapplications and power supply sync issues.

Potentiometers Devices

Rheostat Devices

MCP43X1

MCP42X1

MCP43X2

MCP42X2

TABLE 8-2: PACKAGE FOOTPRINT (1) Package Package Footprint

Pins Type Code

Dimensions (mm)

Are

a (m

m2 )

Rel

ativ

e A

rea

X Y

14 TSSOP ST 5.10 6.40 32.64 2.04

20QFN ML 4.00 4.00 16.00 1TSSOP ST 6.60 6.40 42.24 2.64

Note 1: Does not include recommended landpattern dimensions.


MCP433X/435X

9.0 DEVELOPMENT SUPPORT

9.1 Development ToolsSeveral development tools are available to assist inyour design and evaluation of the MCP43XX devices.The currently available tools are shown in Table 9-1.

These boards may be purchased directly from theMicrochip web site at www.microchip.com.

9.2 Technical DocumentationSeveral additional technical documents are available toassist you in your design and development. Thesetechnical documents include Application Notes,Technical Briefs, and Design Guides. Table 9-2 showssome of these documents.

TABLE 9-1: DEVELOPMENT TOOLS Board Name Part # Supported Devices20-pin TSSOP and SSOP Evaluation Board TSSOP20EV MCP43XXMCP4361 Evaluation Board (1) MCP43XXEV MCP4361MCP42XX Digital Potentiometer PICtail™ Plus DemoBoard

MCP42XXDM-PTPLS MCP42XX

MCP4XXX Digital Potentiometer Daughter Board (2) MCP4XXXDM-DB MCP42XXX, MCP42XX, MCP4021and MCP4011

Note 1: This Evaluation Board is planned to be available by March 2010. This board uses the TSSOP20EV PCBand requires the PICkit™ Serial Analyzer (see User’s Guide for details). This kit also includes 1 blankTSSOP20EV PCB.

2: Requires the use of a PICDEM™ Demo board (see User’s Guide for details).

TABLE 9-2: TECHNICAL DOCUMENTATION ApplicationNote Number

Title Literature #

AN1080 Understanding Digital Potentiometers Resistor Variations DS01080AN737 Using Digital Potentiometers to Design Low-Pass Adjustable Filters DS00737AN692 Using a Digital Potentiometer to Optimize a Precision Single Supply Photo Detect DS00692AN691 Optimizing the Digital Potentiometer in Precision Circuits DS00691AN219 Comparing Digital Potentiometers to Mechanical Potentiometers DS00219— Digital Potentiometer Design Guide DS22017— Signal Chain Design Guide DS21825

MCP433X/435X


NOTES:


MCP433X/435X

10.0 PACKAGING INFORMATION

10.1 Package Marking Information

Legend: XX...X Customer-specific informationY Year code (last digit of calendar year)YY Year code (last 2 digits of calendar year)WW Week code (week of January 1 is week ‘01’)NNN Alphanumeric traceability code Pb-free JEDEC designator for Matte Tin (Sn)* This package is Pb-free. The Pb-free JEDEC designator ( )

can be found on the outer packaging for this package.

Note: In the event the full Microchip part number cannot be marked on one line, it willbe carried over to the next line, thus limiting the number of availablecharacters for customer-specific information.

3e

3e

14-Lead TSSOP

XXXXXXXXYYWW

NNN

Example

4352502E1004

256

XXXXX

20-Lead QFN (4x4)

XXXXXX

YYWWNNN

Example

XXXXXX

4351502EML

256^ 3̂e

20-Lead TSSOP

XXXXXXXXXXXXX NNN

Example

1004

YYWW

4351502EST 256

1004^ 3̂e

MCP433X/435X


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MCP433X/435X


NOTES:


MCP433X/435X

APPENDIX A: REVISION HISTORY

Revision A (March 2010)• Original Release of this Document.

Note: Original TSSOP-20 device samples used theexample marking shown in Figure A-1. Future devicesamples will usE the part marking shown in Section 10.

Figure A-1: Old example TSSOP-20 device marking.

Example

MCP4351EST 256

1004^ 3̂e

MCP433X/435X


NOTES:


MCP433X/435X

APPENDIX B: CHARACTERIZATION DATA ANALYSIS

Some designers may desire to understand the deviceoperational characteristics outside of the specifiedoperating conditions of the device.

Applications where the knowledge of the resistornetwork characteristics could be useful include batterypowered devices and applications that experiencebrown-out conditions.

In battery applications the application voltage decaysover time until new batteries are installed. As thevoltage decays, the system will continue to operate. Atsome voltage level, the application will be below itsspecified operating voltage range. This is dependenton the individual components used in the design. It isstill useful to understand the device characteristics toexpect when this low-voltage range is encountered.Unlike a microcontroller which can use an externalsupervisor device to force the controller into the Resetstate, a digital potentiometer’s resistance characteristicis not specified. But understanding the operationalcharacteristics can be important in the design of theapplications circuit for this low-voltage condition.

Other application system scenarios where understand-ing the low-voltage characteristics of the resistor net-work could be important is for system brown outconditions.

For the MCP433X/435X devices, the analog operationis specified at a minimum of 2.7V. Device testing hasTerminal A connected to the device VDD (forpotentiometer configuration only) and Terminal Bconnected to VSS.

B.1 Low-Voltage OperationThis appendix gives an overview of CMOSsemiconductor characteristics at lower voltages. This isimportant so that the 1.8V resistor networkcharacterization graphs of the MCP433X/435X devicescan be better understood.

For this discussion, we will use the 5 k device data.This data was chosen since the variations of wiperresistance has much greater implications for deviceswith smaller RAB resistances.

Figure B-1 shows the worst case RBW error from theaverage RBW as a percentage, while Figure B-2 showsthe RBW resistance verse wiper code graph. Nonlinearbehavior occurs at approximately wiper code 160. Thisis better shown in Figure B-2, where the RBWresistance changes from a linear slope. This change isdue to the change in the wiper resistance.

FIGURE B-1: 1.8V Worst Case RBW Error from Average RBW (RBW0-RBW3) vs. Wiper Code and Temperature (VDD = 1.8V, IW = 190 µA).

FIGURE B-2: RBW vs. Wiper Code And Temperature (VDD = 1.8V, IW = 190 µA).

-7.00%

-6.00%

-5.00%

-4.00%

-3.00%

-2.00%

-1.00%

0.00%

1.00%

2.00%

0 32 64 96 128 160 192 224 256

Wiper Code

Erro

r %

-40C+25C+85C+125C

0

1000

2000

3000

4000

5000

6000

7000

0 32 64 96 128 160 192 224 256Wiper Code

Res

ista

nce

(�)

-40C+25C+85C+125C

MCP433X/435X


Figure B-3 and Figure B-4 show the wiper resistancefor VDD voltages of 5.5, 3.0, 1.8 Volts. These graphsshow that as the resistor ladder wiper node voltage(VWCn) approaches the VDD/2 voltage, the wiperresistance increases. These graphs also show thedifferent resistance characteristics of the NMOS andPMOS transistors that make up the wiper switch. Thisis demonstrated by the wiper code resistance curve,which does not mirror itself around the mid-scale code(wiper code = 128).

So why is the RW graphs showing the maximumresistance at about mid-scale (wiper code = 128) andthe RBW graphs showing the issue at code 160?

This requires understanding low-voltage transistorcharacteristics as well as how the data was measured.

FIGURE B-3: Wiper Resistance (RW) vs. Wiper Code and Temperature (VDD = 5.5V, IW = 900 UA; VDD = 3.0V,IW = 480 µA).

FIGURE B-4: Wiper Resistance (RW) vs. Wiper Code and Temperature (VDD = 1.8V, IW = 260 µA).

The method in which the data was collected isimportant to understand. Figure B-5 shows thetechnique that was used to measure the RBW and RWresistance. In this technique Terminal A is floating andTerminal B is connected to ground. A fixed current isthen forced into the wiper (IW) and the correspondingwiper voltage (VW) is measured. Forcing a knowncurrent through RBW (IW) and then measuring thevoltage difference between the wiper (VW) andTerminal A (VA), the wiper resistance (RW) can becalculated, see Figure B-5. Changes in IW current willchange the wiper voltage (VW). This may effect thedevice’s wiper resistance (RW).

FIGURE B-5: RBW and RW Measurement.Figure B-6 shows a block diagram of the resistornetwork where the RAB resistor is a series of 256 RSresistors. These resistors are polysilicon devices. Eachwiper switch is an analog switch made up of an NMOSand PMOS transistor. A more detailed figure of thewiper switch is shown in Figure B-7. The wiperresistance is influenced by the voltage on the wiperswitches nodes (VG, VW and VWCn). Temperature alsoinfluences the characteristics of the wiper switch, seeFigure B-4.

The NMOS transistor and PMOS transistor havedifferent characteristics. These characteristics as wellas the wiper switch node voltages determine the RWresistance at each wiper code. The variation of eachwiper switch’s characteristics in the resistor network isgreater then the variation of the RS resistors.

The voltage on the resistor network node (VWCn) isdependent upon the wiper code selected and thevoltages applied to VA, VB and VW. The wiper switch VGvoltage to VW or VWCn voltage determines how stronglythe transistor is turned on. When the transistor isweakly turned on the wiper resistance RW will be high.When the transistor is strongly turned on, the wiperresistance (RW) will be in the typical range.

20406080

100120140160180200220

0 64 128 192 256Wiper Code

Res

ista

nce

(�)

-40C @ 3.0V +25C @ 3.0V +85C @ 3.0V +125C @ 3.0V-40C @5.5V +25C @ 5.5V +85C @ 5.5V +125C @ 5.5V

20

520

1020

1520

2020

0 64 128 192 256Wiper Code

Res

ista

nce

(�)

-40C @ 1.8V

+25C @ 1.8V

+85C @ 1.8V

+125C @ 1.8V

A

B

W

IW

VW

floating

RBW = VW/IW

VA

VB RW = (VW-VA)/IW


MCP433X/435X

FIGURE B-6: Resistor Network Block Diagram.The characteristics of the wiper is determined by thecharacteristics of the wiper switch at each of theresistor networks tap points. Figure B-7 shows anexample of a wiper switch. As the device operationalvoltage becomes lower, the characteristics of the wiperswitch change due to a lower voltage on the VG signal.

Figure B-7 shows an implementation of a wiper switch.When the transistor is turned off, the switch resistanceis in the Giga s. When the transistor is turned on, theswitch resistance is dependent on the VG, VW andVWCn voltages. This resistance is referred to as RW.

FIGURE B-7: Wiper Switch.

So looking at the wiper voltage (VW) for the3.0V and 1.8V data gives the graphs in Figure B-8 andFigure B-9. In the 1.8V graph, as the VW approaches0.8V, the voltage increases nonlinearly. Since V = I * R,and the current (IW) is constant, it means that thedevice resistance increased nonlinearly at aroundwiper code 160.

FIGURE B-8: Wiper Voltage (VW) vs. Wiper Code (VDD = 3.0V, IW = 190 µA).

FIGURE B-9: Wiper Voltage (VW) vs. Wiper Code (VDD = 1.8V, IW = 190 µA).

RS

A

RS

RS

RS

B

RW (1)

W

RW (1)

RW (1)

RW (1)

RW (1)

Note 1: The wiper resistance is dependent onseveral factors including, wiper code,device VDD, Terminal voltages (on A, Band W), and temperature.

RAB

NMOSPMOS

N0

Nn-1

N1

Nn

Nn-2

Nn-3

VW

VB

VA

VWC(n-2)

DVG

Note 1: Wiper Resistance (RW) depends on thevoltages at the wiper switch nodes (VG, VW and VWCn).

RW (1)

NMOS

PMOSNWC Wiper

VG (VDD/VSS)

“gate”

“gate”

VW VWCn

0.0

0.2

0.4

0.6

0.8

1.0

1.2

0 32 64 96 128 160 192 224 256Wiper Code

Wip

er V

olta

ge (V

)

-40C+25C+85C+125C

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

0 32 64 96 128 160 192 224 256Wiper Code

Wip

er V

olta

ge (V

)

-40C+25C+85C+125C

MCP433X/435X


Using the simulation models of the NMOS and PMOSdevices for the MCP43XX analog switch (Figure B-10),we plot the device resistance when the devices areturned on. Figure B-11 and Figure B-12 show theresistances of the NMOS and PMOS devices as theVIN voltage is increased. The wiper resistance (RW) issimply the parallel resistance on the NMOS and PMOSdevices (RW = RNMOS || RPMOS). Below the thresholdvoltage for the NMOS ad PMOS devices, theresistance becomes very large (Giga s). In thetransistors active region, the resistance is much lower.For these graphs, the resistances are on differentscales. Figure B-13 and Figure B-14 only plots theNMOS and PMOS device resistance for their activeregion and the resulting wiper resistance. For thesegraphs, all resistances are on the same scale.

FIGURE B-10: Analog Switch.

FIGURE B-11: NMOS and PMOS Transistor Resistance (RNMOS, RPMOS) and Wiper Resistance (RW) VS. VIN (VDD = 3.0V).




RW

NMOS

PMOS

VG (VDD/VSS)

“gate”

“gate”

VOUT VIN

0.00E+00

5.00E+09

1.00E+10

1.50E+10

2.00E+10

2.50E+10

3.00E+10

0.0 0.3 0.6 0.9 1.2 1.5 1.8VIN Voltage

NM

OS

and

PMO

S R

esis

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e (�

)

0

500

1000

1500

2000

2500

Wip

er R

esis

tanc

e (�

)RPMOS

RNMOS RW

PMOS Theshold

NMOS Theshold

0.00E+00

1.00E+09

2.00E+09

3.00E+09

4.00E+09

5.00E+09

6.00E+09

7.00E+09

0.0 0.6 1.2 1.8 2.4 3.0VIN Voltage

NM

OS

and

PMO

S R

esis

tanc

e (�

)

0

20

40

60

80

100

120

140

160

Wip

er R

esis

tanc

e (�

)RPMOS

RNMOS

RW

PMOS Theshold

NMOS Theshold

0

50

100

150

200

250

300

0.0 0.6 1.2 1.8 2.4 3.0VIN Voltage

Res

ista

nce

(�)

RPMOS RNMOS

RW

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

0.0 0.3 0.6 0.9 1.2 1.5 1.8VIN Voltage

Res

ista

nce

(�)

RPMOS RNMOS

RW


MCP433X/435XB.2 Optimizing Circuit Design for Low-

Voltage CharacteristicsThe low-voltage nonlinear characteristics can beminimized by application design. The section will showtwo application circuits that can be used to control aprogrammable reference voltage (VOUT).

Minimizing the low-voltage nonlinear characteristics isdone by keeping the voltages on the wiper switchnodes at a voltage where either the NMOS or PMOStransistor is turned on.

An example of this is if we are using a digital potentiom-eter for a voltage reference (VOUT). Lets say that wewant VOUT to range from 0.5 * VDD to 0.6 * VDD.

In example implementation #1 (Figure B-15) wewindow the digital potentiometer using resistors R1 andR2. When the wiper code is at full scale the VOUTvoltage will be 0.6 * VDD, and when the wiper code isat zero scale the VOUT voltage will be 0.5 * VDD.Remember that the digital potentiometers RAB variationmust be included. Table B-1 shows that the VOUT volt-age can be selected to be between 0.455 * VDD and0.727 * VDD, which includes the desired range. Withrespect to the voltages on the resistor network node, at1.8V the VA voltage would range from 1.29V to 1.31Vwhile the VB voltage would range from 0.82V to 0.86V.These voltages cause the wiper resistance to be in thenonlinear region (see Figure B-12). In Potentiometermode, the variation of the wiper resistance is typicallynot an issue, as shown by the INL/DNL graph(Figure 2-7).

In example implementation #2 (Figure B-16) we usethe digital potentiometer in Rheostat mode. The resis-tor ladder uses resistors R1 and R2 with RBW at thebottom of the ladder. When the wiper code is at fullscale, the VOUT voltage will be 0.6 * VDD and whenthe wiper code is at full scale the VOUT voltage will be 0.5 * VDD. Remember that the digital potentiometersRAB variation must be included. Table B-2 shows thatthe VOUT voltage can be selected to be between 0.50 *VDD and 0.687 * VDD, which includes the desiredrange. With respect to the voltages on the resistor net-work node, at 1.8V the VW voltage would range from0.29V to 0.38V. These voltages cause the wiperresistance to be in the linear region (see Figure B-12).

FIGURE B-15: Example Implementation #1.

TABLE B-1: EXAMPLE #1 VOLTAGE CALCULATIONS

Variation

Min Typ Max

R1 12,000 12,000 12,000R2 20,000 20,000 20,000RAB 8,000 10,000 12,000VOUT (@ FS) 0.714 VDD 0.70 VDD 0.727 VDD VOUT (@ ZS) 0.476 VDD 0.50 VDD 0.455 VDD VA 0.714 VDD 0.70 VDD 0.727 VDD VB 0.476 VDD 0.50 VDD 0.455 VDD Legend: FS – Full Scale, ZS – Zero Scale

A

B

WVW

VA

VB

R1

R2

VOUT

MCP433X/435X


FIGURE B-16: Example Implementation #2.

TABLE B-2: EXAMPLE #2 VOLTAGE CALCULATIONS

Variation

Min Typ Max

R1 10,000 10,000 10,000R2 10,000 10,000 10,000RBW (max) 8,000 10,000 12,000VOUT (@ FS) 0.667 VDD 0.643 VDD 0.687 VDD VOUT(@ ZS) 0.50 VDD 0.50 VDD 0.50 VDD VW (@ FS) 0.333 VDD 0.286 VDD 0.375 VDD VW (@ ZS) VSS VSS VSS Legend: FS – Full Scale, ZS – Zero Scale

A

B

W VW

VA

R1

R2VOUT

VB


MCP433X/435X

PRODUCT IDENTIFICATION SYSTEMTo order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.

PART NO. X /XX-XXX

Resistance PackageTemperatureRange

Device

Device: MCP4331: Quad Volatile 7-bit PotentiometerMCP4331T: Quad Volatile 7-bit Potentiometer

(Tape and Reel)MCP4332: Quad Volatile 7-bit RheostatMCP4332T: Quad Volatile 7-bit Rheostat

(Tape and Reel)MCP4351: Quad Volatile 8-bit PotentiometerMCP4351T: Quad Volatile 8-bit Potentiometer

(Tape and Reel)MCP4352: Quad Volatile 8-bit RheostatMCP4352T: Quad Volatile 8-bit Rheostat

(Tape and Reel)

Resistance Version:

502 = 5 k 103 = 10 k 503 = 50 k 104 = 100 k

Temperature Range:

E = -40C to +125C (Extended)

Package: ST = Plastic Thin Shrink Small Outline (TSSOP), 14/20-lead

ML = Plastic Quad Flat No-lead (4x4 QFN), 20-lead

Examples:a) MCP4331-502E/XX: 5 k 20-LD Deviceb) MCP4331T-502E/XX: T/R, 5 k20-LD Devicec) MCP4331-103E/XX: 10 k, 20-LD Deviced) MCP4331T-103E/XX: T/R, 10 k, 20-LD Devicee) MCP4331-503E/XX: 50 k, 20-LD Devicef) MCP4331T-503E/XX: T/R, 50 k, 20-LD Deviceg) MCP4331-104E/XX: 100 k, 20-LD Deviceh) MCP4331T-104E/XX: T/R, 100 k,

20-LD Device

a) MCP4332-502E/XX: 5 k 14-LD Deviceb) MCP4332T-502E/XX: T/R, 5 k14-LD Devicec) MCP4332-103E/XX: 10 k, 14-LD Deviced) MCP4332T-103E/XX: T/R, 10 k, 14-LD Devicee) MCP4332-503E/XX: 50 k, 8LD Devicef) MCP4332T-503E/XX: T/R, 50 k, 14-LD Deviceg) MCP4332-104E/XX: 100 k, 14-LD Deviceh) MCP4332T-104E/XX: T/R, 100 k,

14-LD Device

a) MCP4351-502E/XX: 5 k 20-LD Deviceb) MCP4351T-502E/XX: T/R, 5 k20-LD Devicec) MCP4351-103E/XX: 10 k, 20-LD Deviced) MCP4351T-103E/XX: T/R, 10 k, 20-LD Devicee) MCP4351-503E/XX: 50 k, 20-LD Devicef) MCP4351T-503E/XX: T/R, 50 k, 20-LD Deviceg) MCP4351-104E/XX: 100 k, 20-LD Deviceh) MCP4351T-104E/XX: T/R, 100 k,

20-LD Device

a) MCP4352-502E/XX: 5 k 14-LD Deviceb) MCP4352T-502E/XX: T/R, 5 k14-LD Devicec) MCP4352-103E/XX: 10 k, 14-LD Deviced) MCP4352T-103E/XX: T/R, 10 k, 14-LD Devicee) MCP4352-503E/XX: 50 k, 14-LD Devicef) MCP4352T-503E/XX: T/R, 50 k, 14-LD Deviceg) MCP4352-104E/XX: 100 k, 14-LD Deviceh) MCP4352T-104E/XX: T/R, 100 k,

14-LD Device

XX = ST for 14/20-lead TSSOP = ML for 20-lead QFN

Version

MCP433X/435X


NOTES:


Information contained in this publication regarding deviceapplications and the like is provided only for your convenienceand may be superseded by updates. It is your responsibility toensure that your application meets with your specifications.MICROCHIP MAKES NO REPRESENTATIONS ORWARRANTIES OF ANY KIND WHETHER EXPRESS ORIMPLIED, WRITTEN OR ORAL, STATUTORY OROTHERWISE, RELATED TO THE INFORMATION,INCLUDING BUT NOT LIMITED TO ITS CONDITION,QUALITY, PERFORMANCE, MERCHANTABILITY ORFITNESS FOR PURPOSE. Microchip disclaims all liabilityarising from this information and its use. Use of Microchipdevices in life support and/or safety applications is entirely atthe buyer’s risk, and the buyer agrees to defend, indemnify andhold harmless Microchip from any and all damages, claims,suits, or expenses resulting from such use. No licenses areconveyed, implicitly or otherwise, under any Microchipintellectual property rights.

Trademarks

The Microchip name and logo, the Microchip logo, dsPIC, KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro, PICSTART, PIC32 logo, rfPIC and UNI/O are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.

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Analog-for-the-Digital Age, Application Maestro, CodeGuard, dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN, ECONOMONITOR, FanSense, HI-TIDE, In-Circuit Serial Programming, ICSP, Mindi, MiWi, MPASM, MPLAB Certified logo, MPLIB, MPLINK, mTouch, Octopus, Omniscient Code Generation, PICC, PICC-18, PICDEM, PICDEM.net, PICkit, PICtail, REAL ICE, rfLAB, Select Mode, Total Endurance, TSHARC, UniWinDriver, WiperLock and ZENA are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.

SQTP is a service mark of Microchip Technology Incorporated in the U.S.A.

All other trademarks mentioned herein are property of their respective companies.

© 2010, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved.

Printed on recycled paper.

ISBN: 978-1-60932-061-4

Note the following details of the code protection feature on Microchip devices:• Microchip products meet the specification contained in their particular Microchip Data Sheet.

• Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the intended manner and under normal conditions.

• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data Sheets. Most likely, the person doing so is engaged in theft of intellectual property.

• Microchip is willing to work with the customer who is concerned about the integrity of their code.

• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not mean that we are guaranteeing the product as “unbreakable.”

Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of ourproducts. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such actsallow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.

Microchip received ISO/TS-16949:2002 certification for its worldwide headquarters, design and wafer fabrication facilities in Chandler and Tempe, Arizona; Gresham, Oregon and design centers in California and India. The Company’s quality system processes and procedures are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping devices, Serial EEPROMs, microperipherals, nonvolatile memory and analog products. In addition, Microchip’s quality system for the design and manufacture of development systems is ISO 9001:2000 certified.



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