fpga 步进电机控制器.pdf

Application Note AC136 A Stepper Motor Controller in an Actel FPGA I n t r o d u c t i o n MOSFET devices can also be used to drive the stepper motor Stepper motors are electromechanical devices that provide Within the Actel FPGA, four inputs are required to fully accurate incremental rotation. Printer paper feeders, floppy control the stepper motor. The clock (CLK) input drives, and robotic manipulators are popular stepper motor synchronizes the logic and determines the speed of rotation. applications. The most common stepper motor uses four The motor advances one step per clock period; the angle of windings for a four-phase operation. Rotation is effected by rotation of the shaft will depend on the particular motor (the actuating the phases in a specific sequence. Field angle ranges from 1.8 to 90 degrees per step). To determine programmable gate arrays (FPGAs) are ideal for integrating the clock period, consider that the stepper motor torque the control logic for these motors with other system control increases as frequency decreases. The direction (DIR) control logic to minimize device count and board size. input changes the sequence at the outputs (PH1 to PH4) to reverse the motor direction. The enable input (EN) F o u r - P h a s e M o t o r C i r c u i t . determines whether the motor is rotating or holding. The active low reset input (RST) initializes the circuit to ensure A typical four-phase motor