Dear Motor driver masters,
Can you help to check whether we have DRV8908/DRV8912 based stepper motor reference code? The motor customer using is a 2 winding/5 wire stepper motor, and I hope to get a reference code to help customer rotate the motor quickly.
Thanks.
Eric.
Hello Eric,
You mentioned the motor is a 2 winding/ 5 wire stepper motor. I'm assuming you were referring to a 5-wire unipolar stepper motor such as shown in the below snippet.
For driving one stepper in this configuration a minimum of four half-bridges will be needed. Technically only the low side driver is needed for unipolar steppers. Must ensure the current drive capability of each half-bridge LS matches the stepper requirement for each winding. You may have to use the continuous mode without PWM. For this device all transactions for bridge control will be via SPI only. This needs to be taken into account for the controller as SPI transactions could limit the maximum achievable stepping rate.
While we do not have DRV8908/DRV8912 based stepper motor reference code for driving unipolar steppers this application note would be a good reference, https://www.ti.com/lit/an/sloa312/sloa312.pdf.
First customer must decide drive mode either full-step or half-step. Next they must create a truth table as shown in the application note and customize it for this device. Then the truth table must be translated to the SPI control sequence. I hope this helps.
Regards, Murugavel
