115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036 (508) 853-5000

8925

3-PHASE BRUSHLESS DC MOTOR CONTROLLER/DRIVER

WITH LINEAR CURRENT CONTROL

AND POWER DMOS OUTPUTS

Term.

Terminal Name

Function

1

Power DMOS output.

2

LOGIC SUPPLY

3

LOGIC GROUND

Low-level logic ground.

4

Power DMOS output.

6

ENABLE

Active high chip enable.

7–17

POWER GROUND

Power ground and thermal heat sink.

18

External precision resistor for sense-FET current.

19

COMP.

Compensation; error amplifier output.

20

REFERENCE

21

ERROR AMP.

Input that controls the current in the load.

22

LOAD SUPPLY

23

BRAKE

A logic low turns OFF all source drivers and turns ON all sink drivers (shorts the windings to

ground).

24

High-level input from a Hall sensor.

26

High-level input from a Hall sensor.

28

High-level input from a Hall sensor.

29–39

POWER GROUND

Power ground and thermal heat sink.

40

FAULT

A logic low at this output indicates a thermal shutdown, under -voltage fault, or an invalid Hall

input combination.

42

Power DMOS output.

43

TACH

44

POLE

Designates four- or eight-pole motor; Low = 4 pole, High = 8 pole.

FUNCTIONAL DESCRIPTION

of 0.25

Ω. Intrinsic ground clamp and flyback

diodes clamp transient voltage spikes when

switching inductive loads. Internal charge

pump circuitry is used to drive the gates of

the N-channel source drivers to their required

gate voltages.

Current Control. Current in the load is

monitored by an internal sense amplifier that

produces an output current that is approxi-

mately one twelve hundredth that of the load

current (see Figure). This current is output to

V

SEQUENTIAL

LOGIC

CHARGE

PUMP

SENSE

AMPLIFIER

BB

SUB

ERROR

AMPLIFIER

V

SENSE

V

REF

COMP.

+

-

R

1

R

2

Dwg. EP-040

+

_

R

3

R

S

OUT

OUT

I

.

1200

OUT

V

Continued next page...

TERMINAL FUNCTIONS