UCD90320: Does PMBUS_CNTRL pin state matter if no rails use CONTROL for On/Off configuration?

Jonathan Bender

Part Number: UCD90320

Hello,

If no rails are configured to use CONTROL for the On/Off configuration (all Auto or OPERATION only), is it okay for the PMBUS_CNTRL pin to be floating? Does it have any other function in the system?

The preference would be to leave it floating but routed to the PMBus header, so the USB-to-GPIO dongle could still assert CONTROL as necessary for debug purposes.

Thanks,

Jonathan

over 8 years ago

0 Zhiyuan Hu over 8 years ago

TI__Genius 9845 points

It preferably has a pull down resistor.

It has no other function though.

Regards,

Zhiyuan

0 Jonathan Bender over 8 years ago in reply to Zhiyuan Hu

TI__Expert 7895 points

I'm guessing the pull-down preference is to avoid a slightly higher power consumption by that floating input structure?

I noticed UCD90320EVM-783 doesn't have termination on the pin. So I'll advise to pull-down with a 10 kohm to GND, but if it doesn't make it onto the schematic, it's not a cause for concern.

Thanks for the quick answer,

Jonathan

Power management

Power management forum

UCD90320: Does PMBUS_CNTRL pin state matter if no rails use CONTROL for On/Off configuration?