A4988 is a complete microstepping motor driver with built-in translator for easy operation. This product is can work in full-stephalf-step1/41/8 and 1/16 step modes. It operates bipolar stepper motors. Output drive capacity of up to 35 V and 2A. The A4988 includes a fixed off-time current regulatorin slow or mixed decay modes. The A4988 converter is the key to the easy implementation. As long as the "step" input gets one pulseit will drive the motor one microstep (One palse per microstep). There are no phase sequence tableshigh frequency control linesor complex interfaces to program.
In the micro-step operationthe A4988 chopping control automatically selects the current decay mode (Slow or Mixed). In mixed decay modethe device is initially set to a fixed downtime in some fast decaythen the rest of the slow decay downtime. Mixed decay current control scheme results in reduced audible motor noiseincreased step accuracyand reduced power consumption. Internal synchronous rectification control circuitry is provided to improve the pulse-width modulation (PWM) operation power consumption. Internal circuit protection includes: thermal shutdown with hysteresisundervoltage lockout (UVLO)and crossover-current protection. Special power sequencing.