A4975SLBTR-T

• Product Introduction

The A4975 is designed to drive one winding of a bipolar stepper motor in microstep mode. The continuous output current is rated for ±1.5 amps and can operate up to 50 volts. Internal pulse-width modulation (PWM) current control and an internal three-position nonlinear digital-to-analog converter allow the device to control motor current in full-step, half-step, quarter-step, or quarter-step (micro-step) modes. Nonlinear increments minimize the control lines required for microsteps. Microsteps improve step resolution and reduce torque variations and resonance issues at low speeds.

The internal circuitry determines the operating mode of the PWM current control circuit: slow (recirculating) current decay mode, fast (regenerative) current decay mode, or mixed current decay mode. In hybrid current decay mode, the shutdown time is divided into two periods: fast current decay time and fixed shutdown time for slow current decay. Combined with user-selectable current sense resistor and reference voltage, the output current ratio can be selected digitally; Slow, fast, or mixed current decay modes provide users with a variety of different motor controls.

Internal circuit protection includes overheating shutdown with delay, transient suppression diodes, and crossover current protection. No special power-up sequencing is required. The A4975 is available in two power packages: a 16-pin dual-in-line plastic package with a copper heatsink (suffix B) and a 16-pin plastic SOIC with an internal fuse pin (suffix LB). Both packages have well-heated pins and are grounded, eliminating the need for electrical insulation. Both packages are lead-free and feature 100% matte tin-plated pinframes.

• ±1.5 安培连续输出电流
• 50 伏特输出电压额定值
• 内部 PWM 电流控制
• 三位非线性 DAC
• 快、快/慢混合以及慢电流衰减模式
• 内部过热关机电路
• 交叉电流及 UVLO 保护