DRV8912-Q1: VM Supply Overvoltage Protection

translation：

I use 24V power supply to drive the drv8912 chip. When the nSleep pin is set to 1, the nFAULT pin will report an error. When I set EXT_OVP to 1, the error disappears. But after I set the FLT_CLR bit, the OVP bit of the status register IC_STST is still 1. What's going on? In addition, can the OVP threshold be set only to 21V or 33V? Can't it be changed to another value (such as 24V)?

Hi Annie,

When the nFAULT pin reports an error what is the IC_STAT readout data? Does it show OVP error only? See below the OVP threshold specifications. These are the available options. Based on these specifications for 24V supply you must use EXT_OVP = 1b to avoid triggering an OVP. It cannot be changed to other value.

This selection will detect if the voltage has reached max. specified operating voltage and well within abs max. Typically when a BDC motor is stopped its energy (back EMF) gets pumped to VM node often times increasing the VM voltage from what the power supply is providing. OVP will detect such situations and report is as OVP error. Of course if the power supply exceeds the threshold for some reason that would be detected as well. Thanks.

Regards, Murugavel