UCD9222: question of UCD9222 VID

If UCD9222 is configured to "ignore VID input pins and commands", the output voltage is not affected by VID pins.

I believe you may be asking what happens if you have VID implemented but the OE# pin on level translator for the VID lines isn't active, which prevents the VID lines from the processor from reaching the controller.

The rail would power up to the VID Code Init level which has been configured into the controller, the rail will be held at the VID Code Init level for the period of time defined by the Lockout Interval. At the end of the Lockout Interval, the VID lines are expected to be valid.  What happens next will depend on whether it is 4-bit or 6-bit VID. 4-bit VID setting will cause the controller to periodically poll the VID lines, if the OE# is still inactive then it will read the 1111 VID code and transition to this voltage.  For 6-bit VID the rail will remain at the VID Code Init level because the controller would need to see transitions on the VIDS line to clock in the VID level.

It appears the reason OE# cannot be driven low is the pull-up voltage on the VCC1V8_PG signal is VCC1V8_AUX which is insufficient to fully enhance the logic level transistor Q6 (2N7002) which prevents VID_OE# from being pulled to ground.