3961 Datasheet, PDF (1/10 Pages) Allegro MicroSystems – DUAL FULL-BRIDGE PWM MOTOR DRIVER

3961
DUAL FULL-BRIDGE
PWM MOTOR DRIVER
3961
DUAL FULL-BRIDGE PWM MOTOR DRIVER
Designed for pulse-width modulated (PWM) current control of
OUT_1B ¹
24 OUT_2B
bipolar stepper motors, the A3961S— is capable of continuous output
currents to ±800 mA and operating voltages to 45 V. Internal fixed
E₁ ²
SENSE₁ ³
OUT_1A ⁴
T _{VBB1 5}
GROUND 6
C _{GROUND 7}
U _{VREFOUT 8}
D ^{Y VREFIN 9}
L _{RC1 10}
PHASE₁ 11
O _{N ENABLE1 12}
23 E ₂
22 SENSE ₂
21 _OUT2A
20 V _BB2
19 GROUND
18 GROUND
17 I _FULL/PD
16 _{V CC}
15 RC₂
14 PHASE ₂
13 ENABLE₂
PR ^O _{Note the A3961SB (DIP) and the A3961SLB}
(SOIC) are electrically identical and share a
E _{common terminal number assignment.}
D _{C ABSOLUTE MAXIMUM RATINGS}
E _{N Load Supply Voltage, VBB . . . . . . . . . . 45 V}
U _{E Output Current, IOUT . . . . . . . . . . ±800 mA*}
Logic Supply Voltage, V_CC . . . . . . . . . 7.0 V
IN R Logic Input Voltage Range,
V_IN . . . . . . . . . . . -0.3 V to V_CC + 0.3 V
T ^E _{Sense Voltage, VSENSE . . . . . . . . . . . . 1.0 V}
N ^F Reference Output Current,
I_{REF OUT} . . . . . . . . . . . . . . . . . . . 1.0 mA
O ^E _{Package Power Dissipation,}
C ^{R PD . . . . . . . . . . . . . . . . . . . . See Graph}
Operating Temperature Range,
T_A . . . . . . . . . . . . . . . . . -20˚C to +85˚C
IS ^R _{Junction Temperature, TJ . . . . . . . +150˚Câ€} 
Storage Temperature Range,
D _{FO TS . . . . . . . . . . . . . . . . -55˚C to +150˚C}
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. Special
power-up sequencing is not required. Internal circuit protection includes
thermal shutdown with hysteresis, transient-suppression diodes, and
crossover-current protection.
The A3961S— is supplied in a choice of two power packages:
24-pin dual-in-line plastic package with copper heat-sink tabs and
24-lead plastic SOIC with copper heat-sink tabs. In both packages the
power tab is at ground potential and needs no electrical isolation.
FEATURES
s ±800 mA Continuous Output Current Rating
s 45 V Output Voltage Rating
s Internal PWM Current Control, Saturated Sink Drivers
s Internally Generated Precision 2.5 V Reference
s Internal Transient-Suppression Diodes
s Internal Thermal-Shutdown Circuitry
s Crossover-Current Protection, UVLO Protection
— * 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.
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
A3961SB
A3961SLB
PACKAGE
24-Pin DIP
24-Lead SOIC
R_θJA
40°C/W
55°C/W
R_θJT
6°C/W
6°C/W