A4982_V4 Datasheet, PDF (1/20 Pages) Allegro MicroSystems – DMOS Microstepping Driver with Translator And Overcurrent Protection

A4982
DMOS Microstepping Driver with Translator
And Overcurrent Protection
Features and Benefits
▪ Low R_DS(ON) outputs
▪ Automatic current decay mode detection/selection
▪ Mixed and Slow current decay modes
▪ Synchronous rectification for low power dissipation
▪ Internal UVLO
▪ Crossover-current protection
▪ 3.3 and 5 V compatible logic supply
▪ Thin profile QFN and TSSOP packages
▪ Thermal shutdown circuitry
▪ Short-to-ground protection
▪ Shorted load protection
▪ Low current Sleep mode, < 10 μA
▪ No smoke no fire (NSNF) compliance (ET package)
Packages:
32-contact QFN
with exposed thermal pad
5 mm × 5 mm × 0.90 mm
(ET package)
Approximate size
24-pin TSSOP
with exposed thermal pad
(LP Package)
Description
The A4982 is a complete microstepping motor driver with
built-in translator for easy operation. It is designed to operate
bipolar stepper motors in full-, half-, quarter-, and sixteenth-step
modes, with an output drive capacity of up to 35 V and ±2 A.
The A4982 includes a fixed off-time current regulator which
has the ability to operate in Slow or Mixed decay modes.
The ET package meets customer requirements for no smoke
no fire (NSNF) designs by adding no-connect pins between
critical output, sense, and supply pins. So, in the case of a
pin-to-adjacent-pin short, the device does not cause smoke
or fire. Additionally, the device does not cause smoke or fire
when any pin is shorted to ground or left open.
The translator is the key to the easy implementation of the
A4982. Simply inputting one pulse on the STEP input drives
the motor one microstep. There are no phase sequence tables,
high frequency control lines, or complex interfaces to program.
The A4982 interface is an ideal fit for applications where a
complex microprocessor is unavailable or is overburdened.
During stepping operation, the chopping control in the A4982
automatically selects the current decay mode, Slow or Mixed.
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
Continued on the next page…
Typical Application Diagram
Microcontroller or
Controller Logic
V_DD
0.22 μF
0.1 μF
0.1 μF
0.22 μF
5 kΩ
VREG ROSC CP1
VDD
CP2
VCP _VBB1
VBB2
SLEEP
STEP
MS1
MS2
DIR
ENABLE
RESET
VREF
A4982
OUT1A
OUT1B
SENSE1
GND
OUT2A
GND
OUT2B
SENSE2
100 μF
4982-DS Rev. 4