2961

HIGH-CURRENT

HALF-BRIDGE

PRINTHEAD/MOTOR DRIVER

The UDN2961B and UDN2961W are 3.4 A half bridges designed

specifically for driving solenoid printheads, stepper motors, and dc

motors. The UDN2961B/W consists of a power source driver output,

a power sink driver output, a flyback recovery diode, internal current

sensing circuitry, and a user-selectable fixed off-time chopper circuit.

The output drivers are capable of sustaining 45 V with continuous

currents of

±3.4 A and peak transient currents of ±4 A permitted. The

outputs have been optimized for a low output saturation voltage

(typically 2.6 V total source plus sink drops at 3.4 A).

For output current control, load current is sensed internally and

limited by chopping the output driver(s) in a user-selectable fixed off-

time PWM mode. The maximum output current is determined by the

user’s selection of a reference voltage. The MODE pin determines

whether the current control circuitry will chop in a slow current-decay

mode (only the source driver switching) or in a fast current-decay

mode (source and sink switching). A user-selectable blanking window

prevents false triggering of the current control circuitry during

chopping.

The UDN2961B is supplied in a 16-pin dual in-line plastic batwing

package with a copper lead-frame and heat sinkable tabs for improved

power dissipation capabilities. For higher power dissipation require-

ments, the UDN2961W is supplied in a 12-pin single in-line power tab

package.

FEATURES

s 3.4 A, 45 V Source and Sink Drivers

s Internal Current Sensing

s User-Selectable Fixed Off-Time PWM Current Control

s Internal Flyback Diode

s Low Output Saturation Voltage

s Chip Enable

s Fast or Slow Current-Decay Modes

s Programmable Blanking Window

s Internal Thermal Shutdown Circuitry

UDN2961B

HIGH-CURRENT HALF-BRIDGE

PRINTHEAD/MOTOR DRIVER—WITH INTERNAL

CURRENT SENSING AND CONTROL

ABSOLUTE MAXIMUM RATINGS

±3.4 A

±4.0 A

Input Voltage Range,

Package Power Dissipation,

Operating Temperature Range,

Storage Temperature Range,

Output current rating may be restricted to a value

determined by system concerns and factors.

These include: system duty cycle and timing,

ambient temperature, and use of any heatsinking

and/or forced cooling. For reliable operation, the

specified maximum junction temperature should

not be exceeded.

* Fault conditions that produce excessive junction

temperature will activate device thermal shutdown

circuitry. These conditions can be tolerated, but

should be avoided.

Always order by complete part number:

Part Number Package

UDN2961B

16-Pin DIP

UDN2961W

12-Pin Power-Tab SIP

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

V

SOURCE OUT

EMITTER

SINK OUT

NC

GROUND

GROUND

CC

IN

ENABLE

RC

MODE

GROUND

GROUND

V

REF

INPUT

CURRENT-

CONTROL

LOGIC

V

LOAD SUPPLY

LOGIC SUPPLY

BB

Dwg. PP-035

2961