DRV8718S-Q1EVM: Chip Select Pull-Down Current

Joseph Urbanski

Prodigy 30 points

Part Number: DRV8718S-Q1EVM

The chip select (nSCS) of the DRV8718 EVM takes way more current to pull it low than what's in the datasheet.

Datasheet: 50 uA (100 uA max)

Reality: 45 mA!

I'm using the 14 pin MCU to DRV header of the EVM and just shorting the nSCS pin to ground through a current meter.

over 3 years ago

0 Joseph Urbanski over 3 years ago

Prodigy 30 points

Found the issue. The MCU needed to be disconnected from 14 pin header. As per the EVM user guide:

"The MCU can be disconnected from the motor driver in order to drive the latter through an external controller by interfacing with the 14 pin header. To do so, remove the resistors between the MCU and the header that connects the MCU to the motor driver"

0 Shinya Morita over 3 years ago in reply to Joseph Urbanski

TI__Mastermind 48925 points

Hi Joseph,

Thank you for your post. Good to know you found the root cause.

regards

Shinya Morita

Motor drivers

Motor drivers forum

DRV8718S-Q1EVM: Chip Select Pull-Down Current