A3973SLB-T

Part No.:
A3973SLB-T
Download:
Download
Description:
Dual DMOS Full-Bridge Microstepping PWM Motor Driver
File Size:
364 K
Page:
10 Pages
Logo:
Maker:
ALLEGRO [ ALLEGRO MICROSYSTEMS ]
PCB Prototype

July 19, 2018:

A-4455-AZ18A

A6267KLPTR-T

A6E-0104

A-70216-0246

A-70400-0186

A-70475-2177

A-A71395-0164

ACE724

AD006-00

AD7492CB

AD8013

AD8048AR-REEL7

PCB Datasheet:1PCB Datasheet:1PCB Datasheet:1
A3973
Dual DMOS Full-Bridge Microstepping PWM Motor Driver
Features and Benefits
±1 A, 35 V Continuous Output Rating
Low R
DS(on)
DMOS Output Drivers
Optimized Microstepping via 6-Bit Linear DACs
Programmable Mixed, Fast, and Slow Current Decay Modes
4 MHz Internal Oscillator for Digital Timing
Serial-Interface Controls Chip Functions
Synchronous Rectification for Low Power Dissipation
Internal UVLO and Thermal Shutdown Circuitry
Crossover-Current Protection
Precision 2 V Reference
Inputs Compatible with 3.3 or 5 V Control Signals
Sleep and Idle Modes
Description
Designed for pulse-width modulated (PWM) current control
of bipolar microstepping stepper motors, the A3973 is capable
of continuous output currents to ±1 A and operating voltages
to 35 V. Internal fixed off-time PWM current-control timing
circuitry can be programmed via a serial interface to operate
in slow, fast, and mixed current-decay modes.
The desired load-current level is set via the serial port with
two 6-bit linear DACs in conjunction with a reference voltage.
The six bits of control allow maximum flexibility in torque
control for a variety of step methods, from microstepping to
full-step drive. Load current is set in 1.56% increments of the
maximum value.
Synchronous rectification circuitry allows the load current to
flow through the low R
DS(on)
of the DMOS output driver during
the current decay. This feature eliminates the need for external
clamp diodes in most applications, saving cost and external
component count, while minimizing power dissipation.
Internal circuit protection includes thermal shutdown with
hysteresis, transient-suppression diodes, and crossover-current
protection. Special power-up sequencing is not required.
The B package is a 24-lead DIP with two copper batwing power
tabs. The LB is a 24-lead SOICW with four internally fused
leads for enhanced power dissipation. These power tabs and
pins are at ground potential and need no electrical isolation.
The A3973 B and LB packages are electrically identical.
Packages:
Package B, 24-pin DIP with
two batwing power tabs
Package LB, 24 pin SOICW
with 4 fused leads
Not to scale
Pin-out Diagram
CHARGE
PUMP
VCP
CP1
CP2
OUT
1B
LOAD
SUPPLY
1
GROUND
GROUND
SENSE
1
1
2
3
4
5
6
7
8
9
9
10
24
23
22
21
20
19
18
17
16
V
DD
15
14
13
OSC
SLEEP
V
REG
OUT
2B
LOAD
SUPPLY
GROUND
GROUND
SENSE
OUT
2A
LOGIC
SUPPLY
MUX
REF
2
V
BB1
V
BB2
2
6-BIT DAC
& LOGIC
SERIAL PORT
OUT
1A
STROBE
CLOCK
DATA
11
12
6-BIT DAC
& LOGIC
Dwg. PP-069-3
29319.34 Rev. 2