A3972SB Allegro Microsystems Inc, A3972SB Datasheet - Page 9

• Manufacturer Part Number: A3972SB
• Description: IC MOTOR DRIVER PWM DUAL 24-DIP
• Manufacturer: Allegro Microsystems Inc

Specifications of A3972SB

• Applications: Stepper Motor Driver
• Number Of Outputs: 1
• Current - Output: ±1.5A
• Voltage - Load: 15 V ~ 50 V
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: -20°C ~ 85°C
• Mounting Type: Through Hole
• Package / Case: 24-DIP (0.300", 7.62mm)
• Operating Current: 12mA
• Operating Temperature Classification: Commercial
• Package Type: PDIP
• Operating Supply Voltage (min): 4.5V
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (max): 5.5V
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Current Sensing. To minimize inaccuracies in sensing the
I
resistor should have an independent ground return to the ground
terminal of the device. For low-value sense resistors, the IR
drops in the sense resistor’s PCB traces can be signifi cant and
should be taken into account. The use of sockets should be
avoided as they can introduce variation in R
resistance.
Thermal Protection. Circuitry turns off all drivers when the
junction temperature reaches 165°C typically. It is intended
only to protect the device from failures due to excessive junction
temperature and should not imply that output short circuits are
permitted. Thermal shutdown has a hysteresis of approximately
15°C.
Serial Port Write Timing Operation. Data is clocked into
a shift register on the rising edge of CLOCK signal. Normally,
STROBE will be held high, and only will be brought low to
initiate a write cycle. The data is written MSB fi rst, followed
by the word-select bit. Refer to serial port diagram for timing
requirements.
PEAK
A3972
A. Minimum Data Setup Time .......................................15 ns
B. Minimum Data Hold Time ........................................10 ns
C. Minimum Setup Strobe to Clock Rising Edge ........150 ns
D. Minimum Clock High Pulse Width ...........................40 ns
E. Minimum Clock Low Pulse Width ............................40 ns
F. Minimum Setup Clock Rising Edge to Strobe ...........50 ns
G. Minimum Strobe Pulse Width .................................150 ns
H. Minimum Setup Sleep to Strobe Falling ...................50 μs
current level caused by ground-trace IR drops, the sense
STROBE
SLEEP
CLOCK
DATA
H
C
A
D18
B
S
APPLICATIONS INFORMATION
due to their contact
D
Microstepping PWM Motor Driver
E
D17
Layout. The printed wiring board should use a heavy ground
plane. For optimum electrical and thermal performance, the
driver should be soldered directly onto the board. The ground
side of R
the driver. This path should be as short as physically possible
and should not have any other components connected to it. The
load supply pin, V
capacitor (>47 μF is recommended) placed as close to the driver
as is possible.
S
Dual DMOS Full-Bridge
should have an individual path to the ground pin(s) of
D0
BB
, should be decoupled with an electrolytic
F
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
G
Dwg. WP-038-1
9