Stepper motor drive

This design is a stepper motor open-loop driver board, using STC15W408AS microcontroller as the main control, 12V power input, and two A4950 motor drives, with a maximum current of up to 3.5A. The three inputs are isolated by optocoupler, so even if the driver board blows up, it will not blow up the main control. The four DIP switches can adjust the subdivision and current (torque), and the serial port interface is reserved for burning programs or for monitoring and debugging.

The DIP switch is used to adjust the subdivision and current. Subdivision [1:2] = 00: no subdivision, =01: x2 subdivision, =10: x4 subdivision, =11: x8 subdivision. Current[3:4] The current increases sequentially from 00->01->10->11, and the torque also increases sequentially. It can be adjusted according to the actual application. (Be careful to enlarge the heat sink, otherwise the temperature will be too high and the machine will shut down)

Electronic forum link: http://bbs.elecfans.com/jishu_1936215_1_1.html

Finished product picture front:

back:

Application diagram:

overall appearance:

See the video for driving effect: