Part Number Package R
θJA
R
θJT
A3953SB 16-Pin DIP 43°C/W 6°C/W
A3953SLB 16-Lead SOIC 67°C/W 6°C/W
FULL-BRIDGE PWM MOTOR DRIVER
Always order by complete part number:
Note the A3953SB (DIP) and the A3953SLB
(SOIC) are electrically identical and share a
common terminal number assignment.
ABSOLUTE MAXIMUM RATINGS
Load Supply Voltage, V
BB
. . . . . . . . . . 50 V
Output Current, I
OUT
(Continuous) . . . . . . . . . . . . . . ±1.3 A*
Logic Supply Voltage, V
CC
. . . . . . . . . 7.0 V
Logic/Reference Input Voltage Range,
V
IN
. . . . . . . . . . . -0.3 V to V
CC
+ 0.3 V
Sense Voltage, V
SENSE
(V
CC
= 5.0 V) . . . . . . . . . . . . . . . . 1.0 V
(V
CC
= 3.3 V) . . . . . . . . . . . . . . . . 0.4 V
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 temperature
of 150˚C.
† Fault conditions that produce excessive junction
temperature will activate the device’s thermal
shutdown circuitry. These conditions can be
tolerated but should be avoided.
Designed for bidirectional pulse-width modulated (PWM) current control
of inductive loads, the A3953S— is capable of continuous output currents to
±1.3 A and operating voltages to 50 V. Internal fixed off-time PWM current-
control circuitry can be used to regulate the maximum load current to a
desired value. The peak load current limit is set by the user’s selection of an
input reference voltage and external sensing resistor. The fixed off-time pulse
duration is set by a user- selected external RC timing network. Internal circuit
protection includes thermal shutdown with hysteresis, transient-suppression
diodes, and crossover current protection. Special power-up sequencing is not
required.
With the ENABLE input held low, the PHASE input controls load current
polarity by selecting the appropriate source and sink driver pair. The MODE
input determines whether the PWM current-control circuitry operates in a
slow current-decay mode (only the selected source driver switching) or in a
fast current-decay mode (selected source and sink switching). A user-
selectable blanking window prevents false triggering of the PWM current-
control circuitry. With the ENABLE input held high, all output drivers are
disabled. A sleep mode is provided to reduce power consumption.
When a logic low is applied to the BRAKE input, the braking function is
enabled. This overrides ENABLE and PHASE to turn off both source drivers
and turn on both sink drivers. The brake function can be used to dynamically
brake brush dc motors.
The A3953S— is supplied in a choice of two power packages; a 16-pin
dual-in-line plastic package with copper heat-sink tabs, and a 16-lead plastic
SOIC with copper heat-sink tabs. For both package styles, the power tab is at
ground potential and needs no electrical isolation.
FEATURES
a73 ±1.3 A Continuous Output Current
a73 50 V Output Voltage Rating
a73 3 V to 5.5 V Logic Supply Voltage
a73 Internal PWM Current Control
a73 Saturated Sink Drivers (Below 1 A)
a73 Fast and Slow Current-Decay Modes
a73 Automotive Capable
a73 Sleep (Low Current
Consumption) Mode
a73 Internal Transient-
Suppression Diodes
a73 Internal Thermal-
Shutdown Circuitry
a73 Crossover-Current
and UVLO Protection
Data Sheet
29319.8*
3953
MODE
GROUND
GROUND
LOGIC
SUPPLY
PHASE

GROUND

GROUND
RC
SENSE
LOAD
SUPPLY
Dwg. PP-056
BRAKE
REF
LOAD
SUPPLY
V
CC
OUT
B
OUT
A
V
BB
V
BB
LOGIC
ENABLE
1
2
3
4
5
6
7
89
10
11
12
13
14
15
16