INA102

FEATURESl LOW QUIESCENT CURRENT: 750A maxl INTERNAL GAINS: 1, 10, 100, 1000l LOW GAIN DRIFT: 5ppm/C maxl HIGH CMR: 90dB minl LOW OFFSET VOLTAGE DRIFT:

2V/C maxl LOW OFFSET VOLTAGE: 100V maxl LOW NONLINEARITY: 0.01% maxl HIGH INPUT IMPEDANCE: 1010

APPLICATIONSl AMPLIFICATION OF SIGNALS FROM

SOURCES SUCH AS:Strain Gages (Weigh Scale Applications)ThermocouplesBridge Transducers

l REMOTE TRANSDUCER AMPLIFIERl LOW-LEVEL SIGNAL AMPLIFIERl MEDICAL INSTRUMENTATIONl MULTICHANNEL SYSTEMSl BATTERY POWERED EQUIPMENT

DESCRIPTIONThe INA102 is a high-accuracy monolithic instrumen-tation amplifier designed for signal conditioningapplications where low quiescent power is desired.On-chip thin-film resistors provide excellent tempera-ture and stability performance. State-of-the-art laser-trimming technology insures high gain accuracy andcommon-mode rejection while avoiding expensiveexternal components. These features make the INA102ideally suited for battery-powered and high-volumeapplications.The INA102 is also convenient to use. A gain of 1, 10,100, or 1000 may be selected by simply strapping theappropriate pins together. A gain drift of 5ppm/C inlow gains can then be achieved without externaladjustment. When higher-than-specified CMR isrequired, CMR can be trimmed using the pins pro-vided. In addition, balanced filtering can be accom-plished in the output stage.

International Airport Industrial Park Mailing Address: PO Box 11400 Tucson, AZ 85734 Street Address: 6730 S. Tucson Blvd. Tucson, AZ 85706

Tel: (520) 746-1111 Twx: 910-952-1111 Cable: BBRCORP Telex: 066-6491 FAX: (520) 889-1510 Immediate Product Info: (800) 548-6132

Low PowerINSTRUMENTATION AMPLIFIER

ABRIDGED DATA SHEETFor Complete Data Sheet

Call Fax Line 1-800-548-6133Request Document Number 10523

A1

A2

A3

14

2

8

4.44k

404

40.04

5pF

1 16

13

11

5pF

20k20k20k

7

6

15

10

3

4

5

20k20k20k

5pF5pF

12 9

V+ V

1985 Burr-Brown Corporation PDS-523G Printed in U.S.A. October, 1993

SBOS137

SPECIFICATIONSELECTRICALAt TA = +25C with 15VDC power supply and in circuit of Figure 2, unless otherwise noted.

INA102AG INA102CG INA102KP/INA102AUPARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX MIN TYP MAX UNITSGAINRange of Gain 1 1000 * * * * V/VGain Equation, External, 20% G = 1 + (40k/RG)(1) * * V/VError, DC: G = 1 TA = +25C 0.1 0.05 0.15 %

G = 10 TA = +25C 0.1 0.05 0.35 %G = 100 TA = +25C 0.25 0.15 0.4 %G = 1000 TA = +25C 0.75 0.5 0.9 %G = 1 TA = TMIN to TMAX 0.16 0.08 0.21 %G = 10 TA = TMIN to TMAX 0.19 0.11 0.44 %G = 100 TA = TMIN to TMAX 0.37 0.21 0.52 %G = 1000 TA = TMIN to TMAX 0.93 0.62 1.08 %

Gain Temp. CoefficientG = 1 10 5 * ppm/CG = 10 15 10 * ppm/CG = 100 20 15 * ppm/CG = 1000 30 20 * ppm/C

Nonlinearity, DCG = 1 TA = +25C 0.03 0.01 * % of FSG = 10 TA = +25C 0.03 0.01 * % of FSG = 100 TA = +25C 0.05 0.02 * % of FSG = 1000 TA = +25C 0.1 0.05 * % of FSG = 1 TA = TMIN to TMAX 0.045 0.015 * % of FSG = 10 TA = TMIN to TMAX 0.045 0.015 * % of FSG = 100 TA = TMIN to TMAX 0.075 0.03 * % of FSG = 1000 TA = TMIN to TMAX 0.15 0.1 * % of FS

RATED OUTPUT

Voltage RL = 10k (|VCC| 2.5) * * VCurrent 1 * * mAShort Circuit Current(2) 2 * * mAOutput Impedance, G = 1000 0.1 * *

INPUT

OFFSET VOLTAGEInitial Offset(3) TA = +25C 300 300/G 100 200/G * V

INA102AU 500 300/G Vvs Temperature 5 10/G 2 5/G * V/Cvs Supply 40 50/G 10 20/G * V/V

vs Time (20 + 30/G) * * V/moBIAS CURRENTInitial Bias Current

(Each Input) TA = TMIN to TMAX 25 50 6 30 * * nAvs Temperature 0.1 * * nA/Cvs Supply 0.1 * * nA/V

Initial Offset Current TA = TMIN to TMAX 2.5 15 2.5 10 * * nAvs Temperature 0.1 * * nA/C

IMPEDANCEDifferential 1010 || 2 * * || pFCommon-Mode 1010 || 2 * * || pFVOLTAGE RANGERange, Linear Response TA = TMIN to TMAX (|VCC| 4.5) * * VCMR With 1k Source Imbalance

G = 1 DC to 60Hz 80 94 90 * 75 * dBG = 10 DC to 60Hz 80 100 90 * * * dBG = 10 to 1000 DC to 60Hz 80 100 90 * * * dB

NOISEInput Voltage Noise

fB = 0.01Hz to 10Hz 1 * * Vp-pDensity, G = 1000: fO = 10Hz 30 * * nV/Hz

fO = 100Hz 25 * * nV/HzfO = 1kHz 25 * * nV/Hz

Input Current NoisefB = 0.01Hz to 10Hz 25 * * pAp-pDensity: fO = 10Hz 0.3 * * pA/Hz

fO = 100Hz 0.2 * * pA/HzfO = 1kHz 0.15 * * pA/Hz

ORDERING INFORMATION

PRODUCT PACKAGE TEMPERATURE RANGE

INA102AG 16-Pin Ceramic DIP 25C to +85CINA102CG 16-Pin Ceramic DIP 25C to +85CINA102KP 16-Pin Plastic DIP 0C to +70CINA102AU 16-Pin Plastic SOIC 25C to +85C

ABSOLUTE MAXIMUM RATINGSSupply ................................................................................................ 18VInput Voltage Range .......................................................................... VCCOperating Temperature Range ......................................... 25C to +85CStorage Temperature Range: Ceramic .......................... 65C to +150C

Plastic, SOIC .................. 55C to +125CLead Temperature (soldering, 10s) ............................................... +300COutput Short Circuit Duration .................................Continuous to Ground

PIN CONFIGURATION

Offset Adjust10 Gain

100 Gain

1000 Gain

1000 Gain Sense

Gain Sense

Gain Set

CMR Trim

Offset Adjust+In

In

Filter

+V

Output

Common

V

1

2

3

4

5

6

7

8

16

15

14

13

12

11

10

9

CC

CC

x

x

x

x PACKAGE INFORMATIONPACKAGE DRAWING

PRODUCT PACKAGE NUMBER(1)

INA102AG 16-Pin Ceramic DIP 109INA102CG 16-Pin Ceramic DIP 109INA102KP 16-Pin Plastic DIP 180INA102AU 16-Pin SOIC 211

NOTE: (1) For detailed drawing and dimension table, please see end of datasheet, or Appendix C of Burr-Brown IC Data Book.

Top View DIP/SOIC

ELECTRICAL (CONT)INA102AG INA102CG INA102KP/INA102AU

PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX MIN TYP MAX UNITS

DYNAMIC RESPONSE

Small Signal,3dB Flatness VOUT = 0.1Vrms

G = 1 300 * * kHzG = 10 30 * * kHzG = 100 3 * * kHzG = 1000 0.3 * * kHz

Small Signal,1% Flatness VOUT = 0.1Vrms

G = 1 30 * * kHzG = 10 3 * * kHzG = 100 0.3 * * kHzG = 1000 0.03 * * kHz

Full Power, G = 1 to 100 VOUT = 10V, RL = 10k 1.7 2.5 * * * * kHzSlew Rate, G = 1 to 100 VOUT = 10V, RL = 10k 0.1 0.15 * * * * V/sSettling Time RL = 10k, CL = 100pF0.1%: G = 1 10V Step 50 * * s

G = 100 360 * * sG = 1000 3300 * * s

0.01%: G = 1 10V Step 60 * * sG = 100 500 * * sG = 1000 4500 * * s

POWER SUPPLY

Rated Voltage 15 * * VVoltage Range 3.5 18 * * * * VQuiescent Current VO = 0V,

TA = TMIN to TMAX 500 750 * * * * A

TEMPERATURE RANGE

Specification 25 +85 * * 0 +70 CINA102AU 25 +85 C

Operation RL > 50k(2) 25 +85 * * 25 +85 CStorage 65 +150 * * 55 +125 C

*Specification same as for INA102AG.NOTES: (1) The internal gain set resistors have an absolute tolerance of 20%; however, their tracking is 50ppm/C. RG will add to the gain error if gains other than1, 10, 100, or 1000 are set externally. (2) At high temperature, output drive current is limited. An external buffer can be used if required. (3) Adjustable to zero.

WARM-UP DRIFT vs TIME50

40

30

20

10

0

Chan

ge in

Inpu

t Offs

et V

olta

ge (m

V)

0 1 2 3 5

Time (ms)4

GAIN vs FREQUENCY

Gai

n (dB

)

80

60

40

20

0

20

Frequency (Hz)10 1M100 1k 10k 100k

G = 1000

G = 100

G = 10

G = 1 1% Error

VOUT = 0.1Vrms

PAD FUNCTION1 Offset Adjust2 X10 Gain3 X100 Gain4 X1000 Gain5 X1000 Gain Sense6 Gain Sense7 Gain Set8 CMR Trim9 VCC

PAD FUNCTION10* Common11 Output12 +VCC13 Filter14 In15 +In16 Offset Adjust17 (A1 Output)18 (A2 Output)

* Glass covers upper one-third of this pad.Substrate Bias: Electrically connected to V supply.NC: No Connection.

MECHANICAL INFORMATIONMILS (0.001") MILLIMETERS

Die Size 142 x 104 5 3.61 x 2.64 0.13Die Thickness 20 3 0.51 0.08Min. Pad Size 4 x 4 0.10 x 0.10Backing GoldINA102 DIE TOPOGRAPHY

TYPICAL PERFORMANCE CURVESAt +25C and in circuit of Figure 2 unless otherwise noted.

COMMON-MODE REJECTION vs SOURCE IMBALANCE120

100

80

60

40

Com

mon

-Mod

e Re

jectio

n (dB

)

100 1k 10k 100k 1M

Source Resistance Imbalance ( )

RIMB20Vp-p5Hz

10k

G = 10 to 1000

G = 1

COMMON-MODE REJECTION vs FREQUENCY

Com

mon

-Mod

e Re

jectio

n (dB

)

Frequency (Hz)1 100 1k

120

100

80

60

4010

V = 20Vp-pIN0 Source Imbalance

G = 1

G = 10

G = 100G = 1000

POWER SUPPLY REJECTION vs FREQUENCY125

100

75

50

25

0

Pow

er S

uppl

y Re

jectio

n (dB

)

1 10 100 1k 10k

Frequency (Hz)

Gain = 1000

Gain = 100

Gain = 10

Gain = 1

INPUT NOISE VOLTAGE vs FREQUENCY1000

100

101 10 100 1k 10k

Frequency (Hz)

Inpu

t Noi

se V

olta

ge (n

VH

z)

G = 1

G = 10

G = 100, G = 1000

PEAK-PEAK VOLTAGE NOISE vs GAIN1000

100

10

1Tota

l Inp

ut P

refe

rred

Noise

Vol

tage

(Vp

-p)

1 10 100 1000

Gain (V/V)

See Applications SectionR = 0S

R = 1MS

R = 100kS

Bandwidth = 1Hz to 1MHz

RS

500k500k

SETTLING TIME vs GAIN

Settl

ing

Tim

e (m

s)

Gain (V/V)1 10 100 1000

10

1

0.1

0.01

L

RC

L = 10k= 1000pF

0.01%

0.1%1%

STEP RESPONSE15

10

5

0

5

10

15

Out

put V

olta

ge (V

)

0 8

Time (ms)1 2 3 4 5 6 7

G = 1

G = 1000L

RC

L = 10k= 1000pF

QUIESCENT CURRENT vs SUPPLY1000

900800700600500400300200100

0

Quies

cent

Cur

rent

(A)

0 5 10 15 20

Supply Voltage (V)

VO = 10V(no load)

VO = 0

TYPICAL PERFORMANCE CURVES (CONT)At +25C and in circuit of Figure 2 unless otherwise noted.

GeCMCMRR

~

~

~ ~ ~

e2

e1

e0ZaZCM

eCM

ed /2

ed /2

Zd

ZCMea eb

Gain Set

DISCUSSION OFPERFORMANCEINSTRUMENTATION AMPLIFIERSInstrumentation amplifiers are differential-input closed-loopgain blocks whose committed circuit accurately amplifies thevoltage applied to their inputs. They respond mainly to thedifference between the two input signals and exhibit ex-tremely high input impedance, both differentially and com-mon-mode. The feedback networks of this instrumentationamplifier are included on the monolithic chip. No externalresistors are required for gains of 1, 10, 100, and 1000 in theINA102.An operational amplifier, on the other hand, is an open-loop,uncommitted device that requires external networks to closethe loop. While op amps can be used to achieve the samebasic function as instrumentation amplifiers, it is very diffi-cult to reach the same level of performance. Using op ampsoften leads to design tradeoffs when it is necessary to amplifylow-level signals in the presence of common-mode voltageswhile maintaining high-input impedances. Figure 1 shows asimplified model of an instrumentation amplifier that elimi-nates most of the problems associated with op amps.

eO = eA + eBeA = G(e2 e1) = GeD

G(e2 + e1) /2 GeCMCMRR CMRR

eB =

Gain set is pin-programmable for x1, x10, x100, x1000 in the INA102.

eO = GeD +

=

FIGURE 1. Model of an Instrumentation Amplifier.

THE INA102A simplified schematic of the INA102 is shown on the firstpage. A three-amplifier configuration is used to provide thedesirable characteristics of a premium performance instru-mentation amplifier. In addition, INA102 has features notnormally found in integrated circuit instrumentation amplifi-ers.

The input buffers (A1 and A2) incorporate high performance,low-drift amplifier circuitry. The amplifiers are connected inthe noninverting configuration to provide the high input

impedance (1010) desirable in instrumentation amplifierapplications. The offset voltage, and offset voltage versustemperature, are low due to the monolithic design, andimproved even further by state-of-the-art laser-trimmingtechniques.The output stage (A3) is connected in a unity-gain differentialamplifier configuration. A critical part of this stage is thematching of the four 20k resistors which provide thedifference function. These resistors must be initially wellmatched and the matching must be maintained over tempera-ture and time in order to retain good common-mode rejec-tion.All of the internal resistors are made of thin-film nichromeon the integrated circuit. The critical resistors are laser-trimmed to provide the desired high gain accuracy andcommon-mode rejection. Nichrome ensures long-term sta-bility and provides excellent TCR and TCR tracking. Thisprovides gain accuracy and common-mode rejection whenthe INA102 is operated over wide temperature ranges.

USING THE INA102Figure 2 shows the simplest configuration of the INA102.The output voltage is a function of the differential inputvoltage times the gain.A gain of 1, 10, 100, or 1000 is selected by programming pins2 through 7 (see Table I). Notice that for the gain of 1000, aspecial gain sense is provided to preserve accuracy. Al-though this is not always required, gain errors caused byexternal resistance in series with the low value 40.04internal gain set resistor are thus eliminated.

GAIN CONNECT PINS

1 6 to 710 2 to 6 and 7

100 3 to 6 and 71000 4 to 7 and separately 5 to 6

TABLE I. Pin-Programmable Gain Connections.

FIGURE 2. Basic Circuit Connection for the INA102.

INA102

~

+In

In

15

7

6

14

~

e2

VCC

9

11

Gain = 1

Output

1210

1FTantalum

1FTantalum

10k+VCC

Other gains between 1 and 10, 10 and 100, and 100 and 1000can also be obtained by connecting an external resistorbetween pin 6 and either pin 2, 3, or 4, respectively (seeFigure 6 for application).G = 1 + (40/RG) where RG is the total resistance between thetwo inverting inputs of the input op amps. At high gains,where the value of RG becomes small, additional resistance(i.e., relays or sockets) in the RG circuit will contribute to again error. Care should be taken to minimize this effect.

OPTIONAL OFFSET ADJUSTMENT PROCEDUREIt is sometimes desirable to null the input and/or output offsetto achieve higher accuracy. The quality of the potentiometerwill affect the results; therefore, choose one with goodtemperature and mechanical-resistance stability.The optional offset null capabilities are shown in Figure 3. R4adjustment affects only the input stage component of theoffset voltage. Note that the null condition will be disturbedwhen the gain is changed. Also, the input drift will beaffected by approximately 0.31V/C per 100V of inputoffset voltage that is trimmed. Therefore, care should betaken when considering use of the control for removal ofother sources of offset. Output offset correction can beaccomplished with A1, R1, R2, and R3, by applying a voltageto Common (pin 10) through a buffer amplifier. This bufferlimits the resistance in series with pin 10 to minimize CMRerror. Resistance above 0.1 will cause the common-moderejection to fall below 100dB. Be certain to keep this resist-ance low.

INA102

VCC

101M

OPA27

A1

1

16

R2 1k

R1100k

Output OffsetAdjust

+15VDC

15VDC

R3

15mV adjustment at the output.R4

100k

Input Offset Adjust

FIGURE 3. Optional Offset Nulling.

It is important to not exceed the input amplifiers dynamicrange. The amplified differential input signal and its associ-ated common-mode voltage should not cause the output ofA1 or A2 to exceed approximately 12V with 15V supplies,or nonlinear operation will result. To protect against mois-ture, especially in high gain, sealing compound may be used.Current injected into the offset pins should be minimized.

OPTIONAL FILTERINGThe INA102 has provisions for accomplishing filtering withone external capacitor between pins 11 and 13. This single-pole filter can be used to reduce noise outside the signalbandwidth, but with some degradation to AC CMR.When it is important to preserve CMR versus frequency(especially at 60Hz), two capacitors should be used. Theadditional capacitor is connected between pins 8 and 10. Thiswill maintain a balance of impedances in the output stage.Either of these capacitors could also be trimmed slightly, tomaximize CMR, if desired. Note that their ratio tracking willaffect CMR over temperature.

OPTIONAL COMMON-MODE REJECTION TRIMThe INA102 is laser-adjusted during manufacturing to assurehigh CMR. However, if desired, a small resistance can beadded in series with pin 10 to trim the CMR to an improvedlevel. Depending upon the nature of the internal imbalances,either positive or negative resistance value could be required.The circuit shown in Figure 4 acts as a bipolar potentiometerand allows easy adjustment of CMR.

FIGURE 4. Optional Circuit for Externally Trimming CMR.

TYPICAL APPLICATIONSMany applications of instrumentation amplifiers involve theamplification of low-level differential signals from bridgesand transducers such as strain gages, thermocouples, andRTDs. Some of the important parameters include common-mode rejection (differential cancellation of common-modeoffset and noise, see Figure 1), input impedance, offsetvoltage and drift, gain accuracy, linearity, and noise. TheINA102 accomplishes all of these with high precision atsurprisingly low quiescent current. However, in higher gains(>100), the bias current can cause a large offset error at theoutput. This can saturate the output unless the source imped-ance is separated, e.g., two 500k paths instead of one 1Munbalanced input. Figures 5 through 16 show some typicalapplications circuits.

1k

OPA177

1k

20CMRAdjust

1k

1kINA102

Procedure:1. Connect CMV to both inputs.2. Adjust potentiometer for near zero at the output.

10Common~

eCM

15

14

15

4

5

6

7

14

INA10211

ResistanceBridge

V

R R

R R

e1

e1

Shield

eIN

e2

+In

In10

+15V

15V

9

12

1000x 1

16

+15V

OptionalOffset Adjust100k

eOUT = 1000 (e2 e1)

INA102 replaces classical three-op-ampinstrumentation amplifier.

FIGURE 5. Amplification of a Differential Voltage from a Resistance Bridge.

eOUT = G (eIN) RY 4.4k, 404, or 40 in gains Note: Gain drift will be higher than thatG = 1 + (40k/[RG + RY]) of 10, 100, or 1000 respectively. specified with internal resistors only.

RG = (40k RY[G 1]) /(G 1)

15

3

7

6

14

INA10211

Shield

+In

In

10

+15V

15V

9

12

100x

eOUTTransduceror

AnalogSignal

TransformerNoise

(60Hz Hum)

Noise(60Hz Hum)

RG

FIGURE 6. Amplification of a Transformer-Coupled Analog Signal Using External Gain Set.

15

3

7

6

14

INA10211

+In

In

10

+15VDC

+15VDC9

12

10x

G = 100

OPA27

15VDC

+VOFFSETTING

500

1M

SpanAdjust

10k

VFC32/320/62

HCPL-2731

ISOSupply

+15VDC

15VDC

+15VDC +15VDC15VDC

Digital100

4990

15k

KThermocouple

1M

IN914

ColdJunction

Compensation15VDC

100kZero Adjust

+15VDC

15VDC15VDC

Opto-Coupler

Up-ScaleBurn-OutIndication

FIGURE 7. Isolated Thermocouple Amplifier with Cold Junction Compensation.

FIGURE 8. ECG Amplifier or Recorder Preamp for Biological Signals.

INA102

15376

14

+In

In

x10011

eOUT

G = 100

12

910

+9V

100k

100k

eIN

eOUT contains a midscaleDC voltage of +4.5V.

FIGURE 9. Single Supply Low Power Instrumentation Amplifier.

* Does not requireexternal isolationpower supply.

Note that x1000 gain sense has notbeen used to facilitate simple switching.

INA102

1523476

14

+In

In

x10

11

eOUT

1210

1M

eIN

9

+15

VDC

Inpu

t Com

mon

15

VDC

ISO1003650

or3656 *

IsolationBarrier

IsolationAmplifier

722IsolationPowerSupply

15VDC

x1 x100x1000

Bias CurrentReturn Resistor

+15

VDC

Out

put C

omm

on

15VD

C

FIGURE 10. Precision Isolated Instrumentation Amplifier.

15

4

5

6

7

14

INA10211

+In

In

10

+15VDC

15VDC

9

12

1000xG = 1000

eOUT = 1Vp-pto isolation amplifier.RL

RA

LA

eIN = 1mVp-p

* As shown channels 0 and 1 may be used for auto offset zeroing, and gain calibration respectively.

FIGURE 11. Multiple Channel Precision Instrumentation Amplifier with Programmable Gain.

FIGURE 12. 4mA to 20mA Bridge Transmitter Using Single Supply Instrumentation Amplifier.

INA102

10

139

11

15V 15V

PGA102 15

12

34

5eOUT

G = 1, 10, 100

+15V

16

x10 x100Gain Select

678

G = 112

76

+In

In

15

14

15V

+15V +15V

D

D

15V

+15V

D

D

10k

10k

eIN

Input Protection: D = FDH300 (Low Leakage)

FIGURE 13. Programmable-Gain Instrumentation Amplifier Using the INA102 and PGA102.

INA102

INA102

INA102

INA102

PGA100

IN7IN6IN5IN4IN3IN2IN1IN0

INA102

VREF*

eOUT

ControlLogic

ChannelSelect

GainSelect

CPCE

e2

e4

e6

e5

INA102e3

e1

INA102

15376

14

1512

435

XTR110

11314

109

2

G S

D

4mA to 20mA VLRLOPA27+6V

40k

60k

1211

+24V

300

910

+10VREF

40mV

G = 100

+2V to +10V

+24V

2N3055

40 40

20

16

4

I O(m

A)

0VIN (mV)

16

15

4

5

6

7

14

INA10211

10

+15V

15V

9

121000x

eOUT

eIN

Ground Resistance

V1

FIGURE 14. Ground Resistance Loop Eliminator (INA102 senses and amplifies V1 accurately).

Overall Gain = eOUT/eIN = 200

15V

INA102 11

eOUT

+15V

12

376

9

10

15

14

eIN

+In

In

x 100

15V

INA102 11

+15V

12

376

9

10

15

14

+In

In

x 100

FIGURE 15. Differential Input/Differential Output Amplifier (twice the gain of one INA).

CONTROL S1 S2 S3 S4 S5 MODE

1 Closed Closed Open Open Closed Signal Amplification0 Open Open Closed Closed Open Auto-Zeroing

15V

INA102 11

+15V

12

376

9

10

15

14

eIN

+In

In

x 100

OPA111or OPA121

1k

0.1F 1/2DG5043CJ

Reference10

DG5040CJ

16

8

6 eOUT

15V

15 13 14

+15V11

15 13 14

200sControl

1

4

11

16

9

5

1

S2

S4

S5

1/2DG5043CJ

S1

S33

All switches shown inLogic 0 switch state.

FIGURE 16. Auto-Zeroing Instrumentation Amplifier Circuit.

The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumesno responsibility for the use of this information, and all use of such information shall be entirely at the users own risk. Prices and specifications are subject to changewithout notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrantany BURR-BROWN product for use in life support devices and/or systems.

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