The A4989 is a dual full-bridge gate driver with an integrated microstep converter for driving a wide range of high-power industrial bipolar two-phase stepper motors (typically 30 to 500 watts). Motor power is provided by an external N-channel power MOSFET with a supply voltage of 12 to 50 volts.
The unit includes two sinusoidal DACs that generate a reference voltage for two independent fixed downtime pulse-width modulation (PWM) current controllers. It can also provide current regulation for the entire bridge of external power MOSFETs.
The motor stepper is controlled by a two-wire stepper and directional interface, providing complete microstep control in full, 1/2, 1/4, and 1/16 step breakdowns. Capable of operating in slow, hybrid, or fast decay modes, fixed downtime regulators operate to reduce audible motor noise, increase step accuracy, and reduce power consumption.
Converters are key to the ease of implementation of this integrated circuit (IC). A pulse is entered into the Step input to drive the motor to produce a step (full, 1/2, 1/4, or 1/16 step, depending on the microstep selection input). ）。 There are no phase sequence tables, high-frequency control lines, or complex interfaces in the program. This reduces the need for complex microcontrollers.
The bootstrap capacitors provide the supply voltage required for these high-end N-channel MOSFETs. Efficiency is increased by applying synchronous rectification, and integrated crossover control and programmable no-inductive time save power FETs from breakdown.
In addition, cross-current control and internal circuit protection can prevent overheating shutdown and undervoltage protection caused by hysteresis. No special power-up sequencing is required.
It is available in a 38-pin TSSOP (Package LD) package. The package is lead-free and features a 100% matte tin-plated pinframe.
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2 线式步进及方向界面
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N 通道 MOSFET 双路全桥门极驱动器
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在12 至 50 伏特的电源电压范围内操作
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同步整流
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交叉传导保护
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可调混合衰减
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集成正弦 DAC 电流参考
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固定停机时间 PWM 电流控制
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微步时更好地控制低电流
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with A3986 引脚兼容