Allegro A2918EWH, A2918SWV, A2918SWH, A2918EWV Datasheet

DISCONTINUED PRODUCT

— FOR REFERENCE ONLY.

Use UDN2917EB for new design

The A2918SWH and A2918SWV motor drivers are designed
to drive both windings of a bipolar stepper motor or bidirectionally
control two dc motors. All bridges are capable of sustaining 45 V and
include internal pulse-width modulation (PWM) control of the output
current to 1.5 A.

For PWM current control, the maximum output current is
determined by the user’s selection of a reference voltage and sensing
resistor. A PHASE input to each bridge determines load current
direction. Active low ENABLE inputs control the four drivers in
each bridge.

The bridges include both ground clamp and flyback diodes for
protection against inductive transients. Internally generated delays
prevent cross-over currents when switching current direction.
Special power-up sequencing is not required. Thermal protection
circuitry disables the outputs if the chip temperature exceeds safe
operating limits.

The A2918SWH/V are supplied in an 18-lead power-tab package
with staggered lead forming. The tab is internally insulated from the
device and requires no external isolation. The A2918SWH/V are
available for operation from -40°C to +85°C. To order, change the
suffix from 'S–' to 'E–'. These devices are also available on special
order for operation to +125°C.

FEATURES

■ ±1.5 A Continuous Output Current

■ 45 V Output Sustaining Voltage

■ Internal PWM Current Control

■ Low Output Saturation Voltage

■ Internal Clamp Diodes

■ Internal Thermal Shutdown Circuitry

■ Similar to Dual PBL3718 or Dual PBL3770

DUAL FULL-BRIDGE

PWM MOTOR DRIVER

ABSOLUTE MAXIMUM RATINGS

at TJ ≤ +150°C

Motor Supply Voltage, VBB. . . . . . . . . 45 V

Output Current, I

OUT

(tw≤20 µs) . . ±1.75 A

(Continuous) . . . . . . . . . . . . . .

±1.5 A

Logic Supply Voltage, VCC. . . . . . . . . 7.0 V

Logic Input Voltage Range,

V

IN

. . . . . . . . . . . . . . . -0.3 V to +7.0 V

Output Emitter Voltage, VE. . . . . . . . . 1.5 V

Package Power Dissipation,

P

D

. . . . . . . . . . . . . . . . . . . . See Graph

Operating Temperature Range,

T

A

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

Storage Temperature Range,

T

S

. . . . . . . . . . . . . . . -40°C to +150°C

Output current rating may be limited by duty cycle,
ambient temperature, and heat sinking. Under
any set of conditions, do not exceed the specified
peak current rating or a junction temperature of
+150°C.

Always order by complete part number:

Part Number Application

A2918SWH For Horizontal Mount

A2918SWV For Vertical Mount

V

REF

V

CC

V

BB

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

1

2

PWM 1

PWM 2

TSD

Dwg. PP-051

OUT

1A

OUT

1B

OUT

2A

OUT

2B

E

1

E

2

SENSE

1

SENSE

2

GROUND

REFERENCE

LOGIC SPLY

LOAD SPLY

ENABLE

1

ENABLE

2

RC

1

RC

2

PHASE

1

PHASE

2

Data Sheet

29319.24A

2918

2918

DUAL FULL-BRIDGE
PWM MOTOR DRIVER

115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]

FUNCTIONAL BLOCK DIAGRAM

TRUTH TABLE

Enable Phase Out

A

Out

B

LHHL
LLLH

HXZ Z

X = Don’t care
Z = High impedance

V

REF

V

CC

OUT

1A

OUT

1B

OUT

2A

OUT

2B

E

1

E

2

SENSE

1

SENSE

2

GROUND

REFERENCE

LOGIC

SUPPLY

LOAD

SUPPLY

ENABLE

1

ENABLE

2

RC

1

RC

2

PHASE

1

PHASE

2

V

BB

1

–
+

ONE SHOT

SOURCE
DISABLE

÷10

–
+

SOURCE
DISABLE

÷10

2

ONE SHOT

PWM 1

PWM 2

TSD

1816

12

14

13

117 5 2

4

15 10 3 6

8

7

9

11

R

T

R

S

R

S

R

T

R

C

C

T

C

T

C

C

R

C

C

C

Dwg. FP-033

50 75 100 125 150

10

6

4

2

0

ALLOWABLE PACKAGE POWER DISSIPATION IN WATTS

TEMPERATURE IN °C

8

25

Dwg. GP-043

R

= 28

°C

/W

θ

J

A

R = 9

°C/W

θ

J

T

W
Copyright © 1991, 1993, Allegro MicroSystems, Inc.

2918

DUAL FULL-BRIDGE

PWM MOTOR DRIVER

www.allegromicro.com

ELECTRICAL CHARACTERISTICS at TA = +25°C, VBB = 45 V, VCC = 4.75 V to 5.25 V,
V

REF

= 5.0 V (unless otherwise noted).

Limits

Characteristic Symbol Test Conditions Min. Typ. Max. Units

Output Drivers (OUT

A

or OUTB)

Motor Supply Range V

BB

10 — 45 V

Output Leakage Current I

CEX

V

OUT

= V

BB

— <1.0 50 µA

V

OUT

= 0 — <-1.0 -50 µA

Output Sustaining Voltage V

CE(sus)

I

OUT

= ±1.5 A, L = 3.0 mH 45 — — V

Output Saturation Voltage V

CE(SAT)

Sink Driver, I

OUT

= +1.0 A — 0.7 0.8 V

Sink Driver, I

OUT

= +1.5 A — 0.9 1.1 V

Source Driver, I

OUT

= -1.0 A — 1.8 2.0 V

Source Driver, I

OUT

= -1.5 A — 1.9 2.2 V

Clamp Diode Leakage Current I

R

VR = 45 V — <1.0 50 µA

Clamp Diode Forward Voltage V

F

IF = 1.5 A — 1.6 2.0 V

Driver Supply Current I

BB(ON)

Both Bridges ON, No Load — 12 15 mA

I

BB(OFF)

Both Bridges OFF — 8.0 10 mA

Control Logic

Input Voltage V

IN(1)

All Inputs 2.4 — — V

V

IN(0)

All Inputs — — 0.8 V

Input Current I

IN(1)

V

IN

= 2.4 V — <1.0 20 µA

I

IN(0)

VIN = 0.8 V — -3.0 -200 µA

Reference Voltage Range V

REF

Operating 1.5 — V

CC

V

Current Limit Threshold V

REF/VSENSE

At Trip Point 9.5 10 10.5 —

Thermal Shutdown Temp. T

J

— 170 — °C

Total Logic Supply Current I

CC(ON)

VEN = 0.8 V, No Load — 105 140 mA

I

CC(OFF)

VEN = 2.4 V, No Load — 10 12 mA

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

Typical Data is for design information only.