DRV8343S-Q1EVM: There is a phenomenon where the FAULT LED lights up

Hi Koji,

To answer your questions:

1. If you look at Table 9 in the datasheet, the Open Load Active (OLA) only reports a fault to the nFAULT pin when EN_OLA_X=1b. When EN_OLA_X=0b no report is made, and no action is taken for recovery. In both cases, the driver and logic are still active. Disabling the EN_OLA_X bits would suppress the reporting of this fault.
2. This is the correct timing, between GLx HIGH⇒LOW and GHx LOW⇒HIGH.
3. When you power up the driver IC and after you enable the part, could you take a measurement with a DMM of GHx-SHx? Any phase works for this test. Alternatively, a scope capture with SHx and GHx of the same phase on the the same plot would help me accurately answer this question.

Thanks for reaching out!

Best regards,
Omar

Hi Koji-san,

1. The fault LED should not be illuminated if there is no fault reporting in SPI, could you please show us an image of the board and fault LED? At the same time, please take a screenshot of the GUI fault registers 0x0, 0x1, 0x2, and 0x3, these are all fault registers.

3. The architecture of our high side driver allows a small leakage current through the GHx/SHx pins when the charge pump is active (DRV ENABLE high), this leakage current is on the order of ~200uA and will be dissipated as soon as the low side FET is turned on during normal switching. GHx - SHx is the VGS voltage of the high side FET and when the high side FET is OFF then GHx will be internally connected to SHx so no VGS voltage can develop and the high side FET is guaranteed to be OFF.

Best regards,
Omar

Hi Omar-san

Thank you for response.

1.I am requesting my customer.
 Please wait.

3.Let me return to the first question.

If I set ENABLE Hi, is it a specification that GHx outputs a high level when I set ENABLE Hi ?

If it is a specification, is there a way to stop the hi level output ?

Best Regards,

Koji Hayashi

Hi Koji-san,

Glad to help! To further answer question 3, this is a known behavior of the high side gate architecture. There is a small amount of leakage through the high side FET pull up and body diodes, this is why SHx and GHx show voltage. Turning on the low side FETs will dissipate this leakage, but I am going to discuss this with my team tomorrow to see if there are any other good ways to suppress this behavior.

Best regards,
Omar

Hi Omar-san

Thank you for response.

3.This was my customer misunderstanding.

With the Lo output from the microcomputer, GHx was outputting Lo.

I apologize for the inconvenience.

Please ignore question 3.

1.I don't want to upload images, so can we communicate through friend registration or direct email ?

Best Regards,

Koji Hayashi

Hi Koji-san,

Sure, send me a friend request on E2E and we can proceed on question 1 over direct message.

Best regards,
Omar

Hi Omar-san

Thank you for response.

I sent a friend registration request.

Best Regards,

Koji Hayashi

Hi Koji-san,

I have accepted your request and sent you a direct message.

Best regards,
Omar

Hi Omar-san

Thank you for accepting an offer.

Sorry, this error was a misconfiguration of the MCU by my customer.

The Fault LED no longer lights up due to a change in the MCU settings.

I would like to close this thread.

Best Regards,

Koji Hayashi