A4982
DMOS Microstepping Driver with Translator
and Overcurrent Protection
Description (continued)
In Mixed decay mode, the device is set initially to a fast decay for
a proportion of the fixed off-time, then to a slow decay for the
remainder of the off-time. Mixed decay current control results in
reduced audible motor noise, increased step accuracy, and reduced
power dissipation.
Internal synchronous rectification control circuitry is provided
to improve power dissipation during PWM operation. Internal
circuit protection includes: thermal shutdown with hysteresis,
undervoltage lockout (UVLO), and crossover-current protection.
Special power-on sequencing is not required.
The A4982 is supplied in two surface mount package, the ET, a
5 mm × 5 mm, 0.90 mm nominal overall package height QFN
package, and the LP package, a 24-pin TSSOP. Both packages have
exposed pads for enhanced thermal dissipation, and are lead (Pb)
free (suffix –T), with 100% matte tin plated leadframes.
Selection Guide
Part Number
A4982SETTR-T
A4982SLPTR-T
Package
32-pin QFN with exposed thermal pad
24-pin TSSOP with exposed thermal pad
Packing
1500 pieces per 7-in. reel
4000 pieces per 13-in. reel
Absolute Maximum Ratings
Characteristic
Load Supply Voltage
Output Current
Logic Input Voltage
Logic Supply Voltage
VBBx to OUTx
Sense Voltage
Reference Voltage
Operating Ambient Temperature
Maximum Junction
Storage Temperature
V
SENSE
V
REF
T
A
T
J
(max)
T
stg
Range S
Symbol
V
BB
I
OUT
V
IN
V
DD
Notes
Rating
35
±2
–0.3 to 5.5
–0.3 to 5.5
35
0.5
5.5
–20 to 85
150
–55 to 150
Units
V
A
V
V
V
V
V
ºC
ºC
ºC
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
2
ALLEGRO [ ALLEGRO MICROSYSTEMS ]
