power management from texas instruments inc. dc/dc dc/dc dc/dc 24v/ 48v/ few 100v think ‘power...

Akermann Electronic BG JSCPower Management from Texas Instruments Inc.

Module 3: Power Management

Part II: MOSFET and IGBT Drivers

• Purpose, Basic Functions, Benefits

• Replacing discrete Gate Drivers (NPN/PNP Totem pole) with Gate Driver ICs

• Key Spec/Parameters

• Types of Gate Drivers

• Examples

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12.October.2017 - Technical seminar

180

MOSFET and IGBT Gate Drivers

2

Everywhere for efficient

power conversion ! ! !

For Equipment in your Every Day Life For Equipment ‘Behind the Scenes’

(Think ‘Infrastructure’)

IT Infrastructure, Server/Telecom, Industrial, Medical

Consumer/Personal/Home/Office/Automotive Electronics

AC/DC Power Supply - from ‘W’ to ‘kW’

Also….DC/DC Isolated Power Supply….Telecom/Industrial

AC/DC

DC/DC

DC/DC

DC/DC

24V/

48V/

Few 100V

Think ‘Power Conditioning/Conversion’(DC/AC)

Motor Control

Solar Power

UPS

Toys

Motor/Fan/Pump

Power Tools

Small Appliances

What is a Gate Driver ??

Gate Driver is a device which enables FAST turn-ON & turn-OFF of power switch

Gate Driver device applies voltage signal between Gate & Source (VGS) and provides high-current pulse

- To charge/discharge CGS, CGD QUICKLY To turn ON/OFF power MOSFET QUICKLY

Gate Driver Gate Driver

Switch Turn-On Switch Turn-Off

Gate Driver IC – Basic Function

• IN signal – from controller, can be logic level

• Output (OUT pin) of Gate Driver changes state based on Input (IN) signal

• OUT signal High Level (ON state) ~ VDD

• OUT signal in Low Level (OFF state) ~ GND

Input Signal Gate Driver Output Signal

ON

OFFOFF

Controller

Turn

ON

Turn

OFF

Output

Current

Pulse

Charge

Discharge

• High-current pulse delivered by OUT pin for power MOSFET turn ON/OFF

• Charging current = Source Current

• Discharging current = Sink Current

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Traditional Gate Driver Circuits Based on Discrete Devices (NPN/PNP Totem Pole)

NPN/PNP Bipolar

transistor in totem pole

configuration

Replace with

Power MOSFET or IGBT

Gate Driver Devices can effectively replace NPN/PNP Totem Pole:

- Reduce BoM component count

- Reduce PCB space

- Improve reliability

Gate Driver Device

9

Digital Power Application Based on Microcontroller/DSPNPN/PNP Totem Pole Needs ADDITIONAL Level Shifting (3.3V PWM 12V)

3.3V/5V

PWM signal from

Microcontroller or

DSP

Level Shifted

12V signal

NPN/PNP Totem Pole

+

Replace with

Digikey AUP (50ku):

-FMMT618/FMMT718 NPN/PNP =$0.159

-2N7002 MOSFETs = $0.022

Gate Driver Device

Level Shift circuit

12V with High, Peak

Source/Sink current

Micro/DSP

Change Traditional Gate Driver Circuits Based on Discrete Devices to IC

10

NPN/PNP Bipolar

transistor in totem

pole configuration

Gate Driver ICFeature TI UCC2751X Gate Driver NPN/PNP Totem Pole

Gate Driver (Discrete or co-pack example

Zetex ZXGD3003E6)

UVLO Feature Yes No

Output Current Immaterial of Input current Directly proportional to input Base current &

Gain

Level-Shifting

Capability

Yes No, Emitter follower (not compatible with

Digital Power trend, see next slide)

Internal Shoot-

through Protection

Yes, Make before break No, add series resistor to limit current from

Bias supply

Enable Function Yes No

Noise Immunity Excellent, choice of CMOS & TTL Poor, can turn-on if IN voltage > 0.7V

Size 2.90 mm x 1.60 mm (UCC27517) At least double the IC foot print

Prop Delay 12ns (typ) Less than 10ns achievable, depends on

load capacitor

Recommended Max

VDD/Bias

18V Based on choice of NPN/PNP

Technical Comparison

Value Added by Gate Driver IC over Discrete Totem Pole

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• Easy System Design

– Integrated solution shortens design cycle.

– Reduced BOM count saves assembly and test cost.

– Excellent noise immunity reduces design uncertainty.

– Built-in level shift saves additional components.

– Ease of board layout

• Reliability– Less BOM count reduces the failure rate and improves the MTBF.

– Internal shoot through protection prevent system in extreme condition.

– UVLO increase system robustness.

• Higher Efficiency– Current drive capability is not limited to input base current & gain.

• Size– Small form factor saves board size.

Layout Example: Discrete vs Integrated

12

BOM of a typical PFC solution with level shift:

Discrete

1. 4 Transistors

2. 2 Multi-layer Ceramic Capacitor

3. 1 E-Cap

4. 10 Resistors

Gate Driver IC

1. 1 Gate driver IC

2. 2 Multi-layer Ceramic Capacitor

3. 1 E-Cap

4. 2 Resistors

Total 17 components with

0.84 in2 PCB space

Total 5 components with

0.33 in2 PCB space

Types of Gate Drivers

2 Types of Gate Drivers – Based on Switch Position or Arrangement

Low Side Drivers

Used to Drive GND

referenced switches

High side-Low Side Drivers

Used to Drive 2 switches

connected in Bridge Arrangement

High side

Low side

Gate

Driver

Low side

Gate

Driver

Low Side Gate Drivers

• GND of Driver IC is same as Source terminal of

power switch

• Reference level for LO output is GND

Voltage

Level

LI

LO

GND

~ VDD-GND

Dual Channel

• 2 Varieties of Low Side Drivers:

– Single Channel = 1 input, 1 output

– Dual Channel = 2 inputs, 2 outputs

Single Channel

• Used to control 2 switches (H, L) arranged in Bridge configuration

• 2 inputs (HIN, LIN), 2 outputs (HO, LO)

• LO drives L switch

– Source of Lower switch L is same as GND

• HO drives H switch

– Source of Upper switch U is referenced to HS (NOT

referenced to GND) – High Side Source

High Side - Low Side Gate Drivers

H

L

GND

Voltage

Level

GND

HS

LI

LO

HI

HO

~ VDD-GND

~ HB-HS

(same as Low-side

Driver)

NOTE:

• Reference level for LO output is GND

– Reference for HO output is HS

(HO is Level Shifted to HS pin)

• HS, HO, HB are High-Voltage pins in

High side-Low side Drivers

High Voltage pins

(up to 620V in some PNs)

A Special Version of High side-Low side

Driver is a Half-Bridge Driver

– Internal circuit ensures HO and

LO can never be ON

simultaneously

– No risk of cross-conduction

between H and L (also called

Shoot-through)

– Sometimes just 1 IN pin controls

both HO and LO state

IN High = HO High, LO Low

IN Low = HO Low, LO High

H

L

High Side - Low Side Gate Drivers (Half-Bridge Drivers)

Both Types of Gate Drivers Needed in Major Power Electronic Topologies

A

D

C

B

21

Bridge

inverter/

rectifier

A

B

21

Half-Bridge

A

1

Forward,

Flyback,

Boost

A

B

21

Asymmetrical H-Br,

Synchronous Buck,

Boost

A

B

1

Active Clamp

A

B

Two-Switch

Forward

2

1

A B

2

Interleaved Forward,

Push-Pull, Boost,

Center-tapped

rectifier

1

VDD

ENBB

OUTAINA1

2

3

4 5

6

7

OUTB

GND

ENBA

INB

8

CO

NT

RO

L

DRIVE

LO

DRIVE

HI

VDD

UCC27200/1

VSS

LI

HB

HO

HS

LOGND

OUT

INA2

1

2

3 4

5

6 Vdd

INA1 +-

NC

Single Low Side Driver Dual Low Side Drivers

High side-

Low side

Drivers

&

Half-Bridge

Drivers

Key Parameters for LOW SIDE Gate Drivers

Low Side DriversParameter Example

# of

Outputs

Channels

1-Channel, UCC27517 2-Channel, UCC27524

Configurati-

on

Non-Inverting (IN+) Inverting (IN-)OUT in-phase OUT out-of-

with IN -phase with IN

# of

Inputs/Ch

Single Input, UCC27537 Dual Input, UCC27533

(IN or IN+/IN-) (IN+ or IN-)

Type of

Input

Threshold

Logic

TTL (or CMOS/TTL) – Fixed Voltage Threshold CMOS – Threshold level is f(VDD)


Peak

Source/Sink

Current

SYMMETRICAL (ISRC=ISNK), UCC27524

ASYMMETRICAL (ISRCISNK), UCC27511

VCC/VDD

Supply

Range

(Min/Max)

UCC27517

UCC27533 (higher VDD range suited for IGBTs)

Is Enable

function

Available ?

(EN pin)

When EN pin is Low, OUT pin is Low (no matter what is status of IN pin)

Available, UCC27518 Not Available, TPS2828

Single

Output

OR

Split

Output ?

Single Output Split Output

Source/Sink Source from OUTH,

from OUT pin Sink from OUTL pin


Turn-On,

Turn-Off

Propagation

Delay (tD)

OR

Input-to-Output

Propagation

Delay

Rise Time (tr),

Fall Time (tf)

Delay Matching Only for Dual Channel Drivers

Package

Options

Single Channel Driver - SOT-23 5-pin, SOT-23 6-pin, DFN 6-pin (with Thermal Pad)

Dual Channel Driver - SOIC 8-pin, PDIP 8-pin, MSOP 8-pin (with Thermal Pad), DFN 8-pin (with

Thermal Pad)


Recommended

Operating

Temperature

Range

UCC27524

TPS2814

Input Pin

Negative Voltage

Capability

UCC27524

UCC27524A

Key Parameters for HIGH SIDE-LOW SIDE Gate Drivers

High Side-Low side DriversParameter Examples

Boot Voltage ABS MAX Voltage Rating of HB pin

UCC27211

UCC27714

Peak

Source/Sink

Current

Similar consideration as ‘Low Side Driver’ section

VCC or VDD

Range


Configuration High side-Low side Driver: 2 input pins (HI, LI)

Half-Bridge Driver: Single Input pin (IN)

Types of Input

Threshold Logic

TTL (or CMOS/TTL compatible) – Fixed voltage threshold

Psuedo-CMOS – Fixed voltage threshold, higher level, wider hysteresis

High Side-Low side DriversParameter Examples

Is Bootstrap

Diode

integrated

inside Driver

Integrated inside device Not integrated inside device

Voltage Slew

Rate on HS

Propagation

Delay


Rise/Fall time Similar consideration as ‘Low Side Driver’ section

Delay Matching Similar consideration as ‘Low Side Driver’ section

High Side-Low Side DriversParameter Example

Recommended

Operating

Temperature

Range

UCC27211

LM5102

Input Pin

Voltage

Capability

UCC27211

UCC27201

Negative Voltage

on HS pin

(for 600V

drivers)

IRS212864

UCC27714

EXAMPLEsof Gate Driver Usage inDifferent Application Schematics

1

channel

Gate

Driver

1

channel

Gate

Driver

PFC

Controller

2-

Channel

Gate

Driver

PFC

Controller

2-

Channel

Gate

Driver

2-phase

PFC

1-phase

PFC

Server/Telecom/industrial AC-DC Power Supply

PFC Stage

1-phase PFC

or

2-phase PFC

DC/DC Stage

Half-Bridge Converter

or

Full-Bridge Converter~AC

400V

48V – for telecom rectifier

24V/few 100V – for industrial

12V – for server power

DC/DC Half Bridge DC/DC Full Bridge

2

channel

Gate

Driver

2

channel

Gate

Driver

Example of PARALLELED Switches - PFC

1

channel

Gate

Driver

1

channel

Gate

Driver

1

channel

Gate

Driver

1

channel

Gate

Driver

PFC Stage Example: UCC28070 2-Phase PFC EVM (Schematic SLUU312B.pdf)

2-Phase PFC converter needs 1X unit of 2-channel gate driver per system for driving 2 PFC

MOSFETs

300W Interleaved

PFC pre-regulator

• 2xPWMs

operating 180˚ out

of phase

• Average CMC

• Reduces boost

inductor volume

• Reduces EMI filter

size

• Hi-Eff Server and Desktop

Power Supplies

• Telecom Rectifiers

• White Goods and

Industrial Equipment


Dual 4-A Peak High-Speed LS Power-MOSFET Drivers

UCC27324D


Simplified Four-Phase

Application Diagram

Using

2 x UCC28070 DevicesVOUT

Example of PARALLELED Switches

The basic Boost, Flyback and Buck-

boost converters have excellent

self-PFC capability naturally.

Boost and Flyback are especially

suitable for DCM PFC usage (most

preferable by the designers).

UCC25600 Half-Bridge

8-Pin High-Performance Resonant Mode LLC Controller

OR

Applications:

• 100-W to 1kW Power Supplies

• LCD, Plasma, DLP TVs

• Adaptors, Computing and ATX Power Supplies

• Home Audio Systems

• Electronic Lighting Ballasts

UCC25600 Half-Bridge (Schematic SLUR403.pdf)

Replace NPN/PNP Totem

Pole with Gate Driver

DC/DC Stage Example: UCC28950 FULL Bridge EVM (Schematic SLUU421A.pdf)Green Phase-Shifted Full-Bridge Controller with Synchronous Rectification

Dual 4-A Peak High-Speed LS

Power-MOSFET Drivers

UCC27324D

DC/DC Stage Example: UCC28950 FULL Bridge EVM (Schematic SLUU421A.pdf)

2-Channel Gate Driver for SR MOSFET

2-Channel Gate Driver for

Gate Drive Transformer

2-Channel Gate Driver for

Gate Drive Transformer

Gate Drive

Transformer

(for sending signal)

Main Power

Transformer

(for sending power)

Current Sensing

Transformer

(for sensing current)

Green Phase-Shifted Full-Bridge Controller With

Synchronous Rectification• 390VDC In / 12VDC Out

• 2A INPUT / 50A OUTPUT

POUT = 600W

• Sync rectification

(Secondary side)

=> High Eff

• Phase-Shifted Full-Bridge

Converters

• Datacom, Telecom, and

Wireless Base-Station

Power

• Server, Power Supplies

• Industrial Power Systems

• High-Density Power

Architectures

• Solar Inverters, and Electric

VehiclesFULL Bridge converter needs 3X units of 2-channel gate driver per system

- 2X units for 2 Gate Drive Transformers

- 1X Units for 2 SR MOSFETs

39

Single Channel Gate Driver IC for POWER TOOLs

Freewheel

Diode

Single Channel

Low Side

Driver ICs

VBATTERY

Battery

Input Voltage

Power

MOSFET

• DC Brush Motor

• Chopper Motors

High side-Low side Gate Driver IC in Bridge-type Motors

High side-Low

side

Gate Driver ICPower

MOSFET

Power

MOSFET

Battery Voltage

Battery Voltage

High side-Low

side

Gate Driver IC

High side-Low

side Gate

Driver IC

Gate Driver in 3-Phase Inverter Motors

41

Low

Side

Gate

Driver

IC

1-ph

or

2-ph

PFC

IC*

PMSM

AC Induction

3X

700V

Half-Bridge

Gate

Driver

IC

15V Bias

Supply

Generation

Block

C/

DSP

*In newer architectures, PFC control function is delivered by C/DSP, eliminating need for a discrete analog PFC controller

Isolated MOSFET and IGBT Drivers

42

A conceptual power drive system block diagram

Electronic devices and integrated circuits (ICs) used for isolation are called isolators


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46

( CMTI – Common-Mode Transient Immunity )


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48

Type C – ISO Driver

4-A Peak Source,

6-A Peak Sink,

5,7-kVRMS Isolated Dual-Channel Gate Driver

Applications• Isolated Converters in Offline AC-to-DC Power

Supplies

• Server, Telecom, IT and Industrial Infrastructures

• Motor Drive and DC-to-AC Solar Inverters

• LED Lighting

• Inductive Heating

• Uninterruptible Power Supply (UPS)

• HEV and BEV Battery Chargers


49


4-A Peak Source,

6-A Peak Sink,

5,7-kVRMS Isolated Dual-Channel Gate Driver

Common‐Mode Transient

Immunity (CMTI) is one of

three key characteristics

associated with digital

isolators as well as

optocouplers.

CMTI is important because

high SR (high‐frequency)

transients can corrupt data

transmission across the

isolation barrier.

The capacitance across the

barrier (i.e., between the

isolated ground planes)

provides the path for these

fast transients to cross the

isolation barrier and corrupt

the output waveform.


50


During CMTI testing, a pulsed

transient is applied across the

isolated ground planes and the

outputs of the device are monitored

for data disruptions.

The key characteristic of this

transient is its slew rate. In the

case shown in the figure a transient

pulse is applied to the ground on

the left hand side of the isolation

barrier while the outputs of the DUT

on the right hand side of the barrier

are monitored.


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power management from texas instruments inc. dc/dc dc/dc dc/dc 24v/ 48v/ few 100v think ‘power...

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