3952
FULL-BRIDGE PWM MOTOR DRIVER
A3952SB
BRAKE
REF
RC
GROUND
GROUND
LOGIC
SUPPLY
PHASE
ENABLE
1
2
3
4
LOGIC
5
6
7
8
V
BB
V
CC
12
11
10
9
GROUND
SENSE
OUTA
LOAD
SUPPLY
V
BB
16
15
14
13
LOAD
SUPPLY
OUTB
MODE
GROUND
Data Sheet
29319.1*
Designed for bidirectional pulse-width modulated current control of
inductive loads, the A3952S– is capable of continuous output currents
to
±2
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 sink 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 inactive.
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 safely used to dynamically brake brush dc motors.
The A3952S– is supplied in a choice of four power packages. In all
package styles, the batwing/power tab is at ground potential and needs
no isolation. These devices are also available for operation from -40°C
to +125°C. To order, change the suffix from 'S–' to 'K–'.
Dwg. PP-056
Note that the A3952SB (DIP) and the A3952SLB
(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
(t
w
≤
20
µs)
..................................
±
3.5 A
(Continuous) ...............................
±
2.0 A
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
......................
1.5 V
Reference Voltage, V
REF
....................
15 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, heat sinking and/or forced
cooling. 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 device thermal shutdown
circuitry. These conditions can be tolerated but
should be avoided.
FEATURES
s
s
s
s
s
s
s
s
s
±2
A Continuous Output Current Rating
50 V Output Voltage Rating
Internal PWM Current Control
Fast and Slow Current-Decay Modes
Sleep (Low Current Consumption) Mode
Internal Transient Suppression Diodes
Under-Voltage Lockout
Internal Thermal Shutdown Circuitry
Crossover-Current Protection
Always order by complete part number:
Part Number
A3952SB
A3952SEB
A3952SLB
A3952SW
Package
16-Pin DIP
28-Lead PLCC
16-Lead SOIC
12-Pin Power-Tab SIP
R
θJA
43°C/W
42°C/W
67°C/W
36°C/W
R
θJT
6.0°C/W
6.0°C/W
6.0°C/W
2.0°C/W
ALLEGRO [ ALLEGRO MICROSYSTEMS ]
