Allegro A3971SLB Datasheet

3971

Data Sheet

29319.32

ADVANCE INFORMATION

(Subject to change without notice)

May 2, 2000

CONNECTION

LOGIC

GROUND

OUT

LOAD

SUPPLY

GROUND

GROUND

SENSE

OUT

PWM

NO

S

S

CP1

1

NC

2

10

3

4

1A

5

1

V

BB1

6

7

1

8

9

1B

9

10

11

11

1

12

LOGIC

CHARGE PUMP

LOGIC

24

DD

V

23

22

21

20

V

BB2

19

18

17

16

15

14

13

LOGIC
SUPPLY

2

PWM

S

20

OUT

2A

LOAD
SUPPLY

GROUND

GROUND

SENSE

OUT

2B

S

21

V

CP

CP2

Dwg. PP-069-2

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.

Low r
during PWM operation. Internal charge pump circuitry is used to create
a boosted voltage to fully enhance the high-side DMOS switches.

2

Three TTL-compatible logic-input terminals per bridge allow flex­ibility in configuring PWM control.

2

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 electri­cal isolation.

DMOS output drivers provide low power dissipation

DS(on)

ABSOLUTE MAXIMUM RATINGS

at TA = +25°C

Load Supply Voltage, VBB................ 50 V

Output Current, I

Transient (<500 ns) ................... ±5 A

Logic Supply Voltage,

VDD............................................ 7.0 V

Sense Voltage, V
Logic Input Voltage Range,

VIN.................. -0.3 V to V

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

Package Power Dissipation,

PD............................................. 2.2 W

Operating Temperature Range,

TA............................. -20°C to +85°C

Junction Temperature, TJ............. +150°C

Storage Temperature Range,

TS........................... -55°C to +150°C

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 tempera­ture of 150 °C.

OUT

...................... 0.5 V

SENSE

DD

BB

+ 0.3 V

+ 8 V

FEATURES

■ ±2.5 A Load Current Capability per Bridge

■ Parallel Outputs for 5 A Load-Current Capability

■ Low r

Typically 325 mΩ source, 175 mΩ sink

■ Synchronous Rectification via Control Logic

■ Internal Undervoltage Monitor

■ Crossover-Current Protection

■ Source Connections for External Current Sensing

■ Thermal Shutdown Circuitry

Always order by complete part number: A3971SLB .

DS(on)

Outputs

3971

DUAL DMOS
FULL-BRIDGE DRIVER

LOGIC

SUPPLY

V

DD

24

VOLTAGE

REFERENCE

FUNCTIONAL BLOCK DIAGRAM

0.22 µF/100 V

CP1CP2

12

V

REF

LOW SIDE SUPPLY

V

CP

13

CHARGE PUMP

DMOS H-BRIDGE

V

CP

14

V

BB2

20

0.22 µF
50 V

LOAD

SUPPLY

S

S

PWM

PWM

LGND

UVLO &

THERMAL

OUT

2A

21

SHUTDOWN

OUT

2B

16

3

10

10

11

11

1

BRIDGE 1

CONTROL

LOGIC

GATE

17

SENSE

(OPTIONAL)

2

RS, C

S

DRIVE

DMOS H-BRIDGE

22

S

20

15

S

21

23

2

2

BRIDGE 2

CONTROL

LOGIC

5

V

OUT

4

OUT

9

SENSE

8

BB1

1A

1B

(OPTIONAL)

1

R

,

C

S

S

GROUND

6

7

18

19

115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]
Copyright © 2000, Allegro MicroSystems, Inc.

Dwg. FP-050

3971

DUAL DMOS

FULL-BRIDGE DRIVER

ELECTRICAL CHARACTERISTICS at TA = +25°C, VBB = 50 V, VDD = 5.0 V (unless otherwise noted).

Limits

Characteristic Symbol Test Conditions Min. Typ. Max. Units

Load Supply Voltage Range V

Logic Supply Voltage Range V

Load Supply Current I

Logic Supply Current I

Output Drivers

Output Leakage Current I

Output ON Resistance r

DS(on)

Body Diode Forward Voltage V

High-Side Gate Voltage V

Control Logic

Logic Input Voltage V

V

Logic Input Current I

I

Propagation Delay Time t

BB

DD

BB

DD

DSS

F

CP

IN(0)

IN(1)

IN(0)

IN(1)

PD

Operating 10 — 50 V

Operating 4.5 5.0 5.5 V

Operating, each supply, no load — — 3.0 mA

Operating — — 5.0 mA

V

= V

OUT

V

OUT

High-side switch, I

Low-side switch, I

BB

= 0 V — <-1.0 -20 mA

= -2.5 A — 325 375 mΩ

OUT

= 2.5 A — 175 200 mΩ

OUT

— <1.0 20 µA

Source diode, IF = 2.5 A — 1.2 — V

Sink diode, IF = 2.5 A — 1.0 — V

C = 0.22 µF, reference V

BB

6.0 6.5 7.0 V

——0.8V

2.0 — — V

VIN = 0 V — <1.0 -5.0 µA

VIN = 5.0 V — 20 50 µA

50% to 90%:

PWM change to source off — 50 — ns

PWM change to sink off — 60 — ns

PWM change to source on — 565 — ns

PWM change to sink on — 665 — ns

Disable to source on — 150 — ns

Disable to sink on — 250 — ns

Thermal Shutdown Temperature T

Thermal Shutdown Hysteresis ∆T

UVLO Threshold V

UVLO Hysteresis ∆V

J

J

UVLO

UVLO

Increasing V

NOTES: 1. Typical Data is for design information only.

2. Negative current is defined as coming out of (sourcing) the specified device terminal.

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DD

— 165 — °C

—15—°C

3.9 4.15 4.4 V

—0.15— V