Part Number: DRV8234
Good morning everyone!
I'm lab testing a DRV8234, mounted on a DRV8234EVM, and I'm having issues with stall detection. Specifically, the device ignores every Tinrush value I set in the registers and detects a stall at engine startup. What I'd like to do is set a Tinrush of 50ms to allow the engine to reach full throttle, and then enable stall detection.
To enable stall detection and route the stall signal to the FAULT pin, I modified the following settings in the evaluation board's online GUI:
- Disable Ripple Count and Soft Start/Stop, in the Daschboard
- H-bridge control set to PH/EN
- IMODE set to 10b, Current regulation at all times
- SMODE set to 1b, Indication only
- VREF set tu 0.675mV
- STAL DETECTION slider set on ON value
- STALL_REP bit on CONFIG4 register set to 1b, to display the stall on the FAULT pin.
- Set CONFIG1 to 0xE8 and CONGIF2 to 0x01 to set Tinrush to 50ms
In this configuration, stall detection should ignore the first 50 ms of operation. The motor is started by setting the "IN1 Duty Cycle (%)" slider in the GUI to its maximum position, with the IN1 Ramp Rate set to 0 so that the motor instantly starts at maximum speed.
I get signals like the ones below. The yellow signal is the motor current measured with a clamp meter, the blue channel is the VREF, the green channel is IPROPI, and the red channel is the FAULT pin.
The stall is detected as soon as the motor starts, as soon as the IPROPI exceeds VREF, without ignoring the event for 50 ms.
Can anyone suggest a possible error in this configuration?
Regards,
Francesco
