3962
DUAL FULL-BRIDGE
PWM MOTOR DRIVER
3962
Designed for pulse-width modulated (PWM) current control of
bipolar stepper motors, the A3962SLB is capable of continuous output
currents to
±800
mA and operating voltages to 30 V. Internal fixed
off-time PWM current-control circuitry can be used to regulate the
maximum load current to a desired value. An internal precision voltage
reference is provided to improve motor peak-current control accuracy.
The peak load current limit is set by the user’s selection of an external
resistor divider and current-sensing resistors.
The fixed off-time pulse duration is set by user-selected external
RC timing networks. The capacitor in the RC timing network also
determines a user-selectable blanking window that prevents false
triggering of the PWM current control circuitry during switching transi-
tions. This eliminates the need for two external RC filter networks on
the current-sensing comparator inputs.
For each bridge the PHASE input controls load current polarity by
selecting the appropriate source and sink driver pair. For each bridge
the ENABLE input, when held high, disables the output drivers. Spe-
cial power-up sequencing is not required. Internal circuit protection
includes thermal shutdown with hysteresis, transient-suppression
diodes, and crossover-current protection.
The A3962SLB is supplied in a 20-lead plastic SOIC with copper
heat sink tabs. The power tab is at ground potential and needs no
electrical isolation.
Data Sheet
29319.27
DUAL FULL-BRIDGE PWM MOTOR DRIVER
SENSE
1
OUT
1A
LOAD
SUPPLY
GROUND
GROUND
V
REF(IN)
PHASE
1
ENABLE
1
ABSOLUTE MAXIMUM RATINGS
Load Supply Voltage, V
BB
. . . . . . . . .
30 V
Output Current, I
OUT
. . . . . . . . . .
±
800 mA*
Logic Supply Voltage, V
CC
. . . . . . . . .
7.0 V
Logic Input Voltage Range,
V
IN
. . . . . . . . . . .
-0.3 V to V
CC
+ 0.3 V
Sense Voltage, V
SENSE
. . . . . . . . . . . .
1.0 V
Reference Output Current,
I
REF OUT
. . . . . . . . . . . . . . . . . . .
1.0 mA
Package Power Dissipation,
P
D
. . . . . . . . . . . . . . . . . . . .
See Graph
Operating Temperature Range,
T
A
. . . . . . . . . . . . . . . .
-20˚C to +85˚C
Junction Temperature, T
J
. . . . . . .
+150˚C†
Storage Temperature Range,
T
S
. . . . . . . . . . . . . . .
-55˚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 current rating or a junction tempera
ture of 150˚C.
T
C
U
D LY
O N
R O
P
D CE
B
E N
SL
U E
4
IN R
96
T E
3
N F
A
O E
e
C R
e
IS R
S
D O
—
F
2
3
4
5
1
2
19
18
SENSE
2
OUT
2A
V
BB
V
CC
17
LOGIC
SUPPLY
16
GROUND
6
15
GROUND
7
14
13
12
11
V
REF(OUT)
RC
2
RC
1
9
8
9
PWM 1
PWM 2
OUT
1B
1
20
OUT
2B
θ
1
θ
2
PHASE
2
10
ENABLE
2
Dwg. PP-047-1
FEATURES
s
s
s
s
s
s
s
s
±800
mA Continuous Output Current Rating
30 V Output Voltage Rating
Internal PWM Current Control, Saturated Sink Drivers
Internally Generated Precision 2.5 V Reference
Internal Transient-Suppression Diodes
Internal Thermal-Shutdown Circuitry
Crossover-Current Protection, UVLO Protection
Automotive Capable
† Fault conditions that produce excessive junction
temperature will activate the device’s thermal
shutdown circuitry. These conditions can be
tolerated but should be avoided.
Always order by complete part number:
A3962SLB
.
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