DRV8412: driving stepper motor problem for DRV8412

Annie Liu

Part Number: DRV8412
Other Parts Discussed in Thread: DRV8841

Hi team,

Customer uses the DRV8412 to drive a three-phase stepper motor, three-way PWM, OUT has a normal waveform, but the motor does not work. It can be drived normally if he uses the same series DRV8841. Below is the circuit diagram of DRV8412.

over 5 years ago

0 Rick Duncan over 5 years ago

TI__Guru** 114905 points

Hi Annie,

What does "not work" mean?

Does the motor move at all?
Does the FAULT pin assert?
Do the currents in the windings match the DRV8841?
Can you provide scope captures of the AOUT1/AOUT2 voltage and AOUT current of both the DRV8412 and DRV8841?
Can you provide scope captures of the inputs voltages of PWM_A/PWM_B/RESET_AB of the DRV8412 and AIN1/AIN2 of the DRV8841?

All of this information will help determine why the DRV8412 does not drive the motor.

FYI - the DRV8412 does not contain the ability to control the winding current through the stepper motor. External circuitry may be required to control the current or the duty cycle should be adjusted as the current increases and decreases.

The DRV8841 contains the ability to control the current. Please note the Figure 5 of the DRV8841 (motor control circuitry). This circuitry regulates the current by entering the specified decay mode when the desired current level is reached.