Why does the PWRMGT_SCL signal get stuck low during configuration of SmartVID (-V) Intel® Stratix® 10 devices operating in PMBus Slave mode?

Description

You may see the PWRMGT_SCL signal get stuck low during the configuration of a SmartVID (-V) Intel® Stratix® 10 device operating in PMBus Slave mode if the PMBus Master has started the ARA flow before the PWRMGT_ALERT signal has been asserted (driven low) by the Intel Stratix 10 device. 

Resolution

Do not start the ARA flow until after the Intel® Stratix® 10 device has asserted the PWRMGT_ALERT signal. Refer to the Intel® Stratix® 10 Power Management User Guide  for the recommended flow.