3971

DUAL DMOS

FULL-BRIDGE DRIVER

Designed to interface between external PWM control logic and

inductive loads such as relays, solenoids, dc motors, or stepper motors,

each full bridge can operate with output currents to

±2.5 A and operating

voltages to 50 V.

during PWM operation. Internal charge pump circuitry is used to create

a boosted voltage to fully enhance the high-side DMOS switches.

Three TTL-compatible logic-input terminals per bridge allow flex-

ibility in configuring PWM control.

Internal circuit protection includes thermal shutdown with hysteresis,

and crossover-current protection. Special power -up sequencing is not

required.

The A3971SLB is supplied in a 24-lead plastic SOIC with a copper

batwing tab. The power tab is at ground potential and needs no electri-

cal isolation.

FEATURES

I ±2.5 A Load Current Capability per Bridge

I Parallel Outputs for 5 A Load-Current Capability

I Low r

Typically 325 m

Ω source, 175 mΩ sink

I Synchronous Rectification via Control Logic

I Internal Undervoltage Monitor

I Crossover-Current Protection

I Source Connections for External Current Sensing

I Thermal Shutdown Circuitry

ADVANCE INFORMATION

(Subject to change without notice)

May 2, 2000

ABSOLUTE MAXIMUM RATINGS

at TA = +25°C

Load Supply Voltage, V

Output Current, I

OUT

Transient (<500 ns) ...................

±5 A

Logic Supply Voltage,

V

Sense Voltage, V

Logic Input Voltage Range,

V

High-Side Gate Voltage ........... V

Package Power Dissipation,

P

Operating Temperature Range,

T

Junction Temperature, T

Storage Temperature Range,

T

Output duty cycle, ambient temperature, and

heat sinking may limit current rating. Under

any set of conditions, do not exceed the

specified current rating or a junction tempera-

ture of 150

°C.

Always order by complete part number: A3971SLB .

CHARGE PUMP

24

23

22

21

20

19

18

17

16

15

14

13

GROUND

GROUND

LOAD

CP2

Dwg. PP-069-2

1

2

3

4

5

6

7

8

9

12

11

10

9

GROUND

GROUND

NO

CONNECTION

LOGIC

GROUND

CP1

LOAD

NC

LOGIC

SUPPLY