DRV8328: unused nFAULT pin and LSS Pin

Weiwei Su

Part Number: DRV8328

Hi Team,

I'm not planning to use nFAULT pin and low side current sensing, can nFAULT pin left floating or must it connect to a power source? Can I tie it to the GVDD via 10K or 100K?

As for LSS, if low side current sensing is not used, can it be tied directly to the GND? Since MP6530/1 can do that as well and I think DRV8328 is the pin-to-pin compatible device? (VDSLVL is disabled as well)

1 month ago

0 Yara Al Shami 1 month ago

TI__Genius 17035 points

Hello,

Regardless if nFAULT is being used or not it is recommended to pull it up to a 3.3V to 5V supply with a 10kohm resistor. Without this pull up nFAULT might be pulled low and the device will respond to that as if a fault is present.

The VDS monitors rely on LSS to monitor overcurrent events on the low side so it is important to use LSS as the low side source pin.

Regards,

Yara

0 Weiwei Su 1 month ago in reply to Yara Al Shami

Intellectual 260 points

Hi Yara,

I am not planning to use VDS Monitor, do I still need to connect LSS?

+1 Yara Al Shami 1 month ago in reply to Weiwei Su

TI__Genius 17035 points

Hi,

LSS should still be connected to the lowside FETs

https://e2e.ti.com/support/motor-drivers-group/motor-drivers---internal/f/motor-drivers---internal-forum/1535901/drv8328-lss-pin-connection?tisearch=e2e-sitesearch&keymatch=lss#

Regards,

Yara

Power management

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DRV8328: unused nFAULT pin and LSS Pin