2961
HIGH-CURRENT
HALF-BRIDGE
2961
HIGH-CURRENT HALF-BRIDGE
PRINTHEAD/MOTOR DRIVER
PRINTHEAD/MOTOR DRIVER—WITH INTERNAL
CURRENT SENSING AND CONTROL
The UDN2961B and UDN2961W are 3.4 A half bridges designed
UDN2961B
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.
V
V
SINK OUT
EMITTER
1
2
16
15
BB
REF
IN
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).
14 NC
INPUT
GROUND
GROUND
ENABLE
3
4
CURRENT-
CONTROL
LOGIC
GROUND
13
5
6
12 GROUND
V
BB
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.
LOAD SUPPLY
11
SOURCE OUT
RC
7
8
10
9
MODE
V
CC
LOGIC SUPPLY
Dwg. PP-035
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, V . . . . . . . . . . . . . . 45 V
BB
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.
Output Current, I
(continuous) . ±3.4 A
OUT
(t ≤ 20 µs, 10% duty cycle) . . ±4.0 A
w
Logic Supply Voltage, V . . . . . . . . . 7.0 V
CC
Input Voltage Range,
V
IN
. . . . . . . . . . . . . . . -0.3 V to +7.0 V
Package Power Dissipation,
. . . . . . . . . . . . . . . . . . . See Graph
FEATURES
P
D
■ 3.4 A, 45 V Source and Sink Drivers
■ Internal Current Sensing
■ User-Selectable Fixed Off-Time PWM Current Control
■ Internal Flyback Diode
■ Low Output Saturation Voltage
■ Chip Enable
Operating Temperature Range,
T . . . . . . . . . . . . . . . . -20°C to +85°C
A
Junction Temperature, T . . . . . . . +150°C*
J
Storage Temperature Range,
T . . . . . . . . . . . . . . . -55°C to +150°C
S
■ Fast or Slow Current-Decay Modes
■ Programmable Blanking Window
■ Internal Thermal Shutdown Circuitry
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.
Always order by complete part number:
* Fault conditions that produce excessive junction
temperature will activate device thermal shutdown
circuitry. These conditions can be tolerated, but
should be avoided.
Part Number Package
UDN2961B
16-Pin DIP
UDN2961W 12-Pin Power-Tab SIP
ALLEGRO [ ALLEGRO MICROSYSTEMS ]
