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TPS65911: VIO IS WAY TOO HIGH AND CAN'T CHANGE IT

Part Number: TPS65911

I am using the TPS6591133 to power a DM385. I am only using the VIO to power the DVDD_C, VDDA_1P8, VDDA_PCIE_1P8, VDDS_OSC0_1P8, VDDS_OSC1_1P8 of the DM385 and the DVDD of a TLV320AIC3101 audio CODEC. I have verified before getting the board booted that the VIO was 1.8V

I have had 2 boards now have the VIO go up to 3.5V even though the register setting was for 1.8V. When we tried to change it the only setting that works is 3.3V or off. Any of the other settings do nothing an the output stays at 3.5V.

I removed the output EMI filter to isolate it and see if it was the PMIC or something driving it. The output went to 4V with no load so I put a 100 OHM resistor in for a load and it still was 4V. All the other voltages are correct and can be changed.

What would cause this to happen? Any help or ideas would be great.

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