A3979SLPTR-T

The A3979SLP-T is a Microstepping DMOS Motor Driver with built-in translator. It is designed to operate bipolar stepper motors in full, half, quarter and eighth-step modes. It includes a fixed off-time current regulator that has the ability to operate in slow, fast or mixed-decay modes. This current-decay control scheme results in reduced audible motor noise, increased step accuracy and reduced power dissipation. The translator is the key to the easy implementation. Simply inputting one pulse on the STEP input drives the motor one step. There are no phase-sequence tables, high-frequency control lines or complex interfaces to program. The interface is an ideal fit for applications where a complex microprocessor is unavailable or over-burdened. Internal synchronous-rectification control circuitry is provided to improve power dissipation during PWM operation. Internal circuit protection includes thermal shutdown with hysteresis, under voltage lockout and crossover-current protection.

• ±2.5A, 35V Output rating
• Low RDS(on) outputs, 0.28Ω source, 0.22Ω sink typical
• Automatic current decay mode detection/selection
• 3 to 5.5V Logic supply voltage range
• Mixed, fast and slow current decay modes
• Home output
• Synchronous rectification for low power dissipation
• Internal UVLO and thermal shutdown circuitry
• Crossover current protection