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3932

The A3932SEQ is a three-phase brushless DC motor controller. The

A3932’s high current gate drive capability allows driving of a wide range of

power MOSFETs and can support motor supply voltages from 12 to 50V.

The A3932 integrates a bootstrapped high side driver to minimize the

external component count required to drive N-channel MOSFET drivers.

Internal fixed off time PWM current control circuitry can be used to

regulate the maximum load current to a desired value. The peak load current

limit is set by the user’s selection of an input reference voltage and external

sensing resistor. The fixed off time pulse duration is set by a user-selected

external RC timing network. For added flexibility, the PWM input can be

used to provide speed/torque control, allowing the internal current control

circuit to set a maximum current limit.

The A3932 includes optional synchronous rectification. This feature

will short out the current path through the power MOSFETs intrinsic body

diodes during PWM off cycle current decay. This can minimize power

dissipation in the MOSFETs, eliminate the need for external power clamp

diodes, and potentially allow a more economical choice for the MOSFET

drivers.

The A3932 provides commutation logic for Hall sensors configured

for 120-degree spacing. The Hall input pins are pulled up to an internally

generated 5V reference. Power MOSFET protection features includes gate-

source voltage monitor, bootstrap capacitor charging current monitor,

undervoltage monitor, motor lead short to supply or ground, and thermal

shutdown.

FEATURES

n Drives Wide Range of N-channel

MOSFETs

n Sources 1.25A for Gate Turn-On

n Sinks 2.5A for Gate Turn-Off

n Synchronous Rectification

n Power MOSFET Protection

n Adjustable Dead Time for Cross

Conduction Protection

n Fast/Slow Current Decay Modes

n Internal PWM current Control

n PWM Torque Control Input

n Motor Lead Short to Supply

and Ground Protection

n Internal 5V Regulator

n Direction Control

n Brake Input

n Fault Diagnostic Output

n Tachometer Output

n Thermal Shutdown

n Undervoltage Protection

n 32L PLCC Package

8

7

6

5

10

9

12

26

27

28

29

22

25

24

21

CC

GHC

GLB

SB

GHB

CB

SA

PWM

TACH

SENSE

RC

H3

BRAKE

H2

SR

A3932SEQ

11

GLA

13

GHA

ABSOLUTE MAXIMUM RATINGS

at TA = +25°C

VREG (Transient) ......................................... 15 V

Logic Input Voltage Range,

Pins SA/SB/SC, ................................... -5 to 50 V

Pins CA/CB/CC .........................SA/SB/SC+17 V

Package Power Dissipation (TA = +25°C)

Operating Temperature Range,

Storage Temperature Range,

ADVANCED DATASHEET - 03/02/99

(Subject to change without notice)

THREE PHASE POWER

MOSFET CONTROLLER

Always order by complete part number: A3932SEQ