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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
Very thin profile QFN package
Thermal shutdown circuitry
Description
The A4983 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-, eighth, and
sixteenth-step modes, with an output drive capacity of up to
35 V and 鹵2 A. The A4983 includes a fixed off-time current
regulator which has the ability to operate in Slow or Mixed
decay modes.
The translator is the key to the easy implementation of the
A4983. 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 A4983 interface is an ideal fit for applications where a
complex microprocessor is unavailable or is overburdened.
The chopping control in the A4983 automatically selects the
current decay mode (Slow or Mixed). When a signal occurs at
the STEP input pin, the A4983 determines if that step results
in a higher or lower current in each of the motor phases. If
the change is to a higher current, then the decay mode is set
to Slow decay. If the change is to a lower current, then the
current decay is set to Mixed (set initially to a fast decay for
a period amounting to 31.25% of the fixed off-time, then to a
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Package: 28-pin QFN (suffix ET)
Approximate size
Typical Application Diagram
V
DD
0.22
渭F
VREG
VDD
Microcontroller or
Controller Logic
MS1
MS2
MS3
SLEEP
STEP
DIR
RESET
ENABLE
REF
ROSC
VCP CP1
0.1
渭F
CP2
0.1
渭F
V
BB
VBB
VBB
OUT1A
OUT1B
RS1
A4983
OUT2A
OUT2B
RS2
4983DS
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