A3979SLP-T

Overview

The A3979SLP-T is a microstepping DMOS driver with an integrated translator, designed for bipolar stepper motors. It features a 28-pin TSSOP-EP package and supports logic supply voltages from 3.0 V to 5.5 V, with load voltages ranging from 8 V to 35 V. The device provides an output current rating of ±2.5 A and includes automatic current decay mode detection. Key electrical parameters include typical on-resistances of 0.28 Ω (source) and 0.22 Ω (sink). It operates within a junction temperature range of -20°C to 150°C.

Feature Summary

• Integrates a translator for simplified step/direction control without external microprocessor intervention
• Features automatic current decay mode detection and selection for optimized motor performance
• Includes synchronous rectification to minimize power dissipation during operation
• Provides comprehensive protection via internal UVLO, thermal shutdown, and crossover-current prevention

Applications

• Bipolar stepper motor control in office automation equipment
• Motion control systems requiring precise positioning
• General-purpose motor drive applications with limited I/O resources

Procurement Notes

Verify the specific suffix 'T' indicates tape-and-reel packaging configuration. Confirm the absence of the 'L' or 'G' prefixes which may denote different voltage ratings or automotive qualifications. Ensure compatibility with the required 28-TSSOP-EP footprint and verify lead-free status against RoHS requirements before finalizing procurement specifications.

Selection Notes

Select this component when a fully integrated solution with built-in translation is required to reduce system complexity. It is suitable for applications needing up to 2.5 A output current and support for microstepping resolutions including full, half, quarter, and sixteenth steps. Consider the thermal management requirements associated with the TSSOP-EP package for high-current operations.

Part Context

This part belongs to Allegro's A3979 family of microstepping drivers. It shares functional similarities with the A3977 but offers specific electrical characteristics tailored for general-purpose bipolar stepper motor applications. The device integrates both logic and power stages into a single DMOS technology solution.

Replacement Considerations

The A3979SLPTR-T is a direct equivalent variant differing primarily in reel packaging quantity. Verify pinout compatibility if considering alternative Allegro models such as the A3977 or A3983, as interface definitions may vary across the product family.