All power supplies required by the EVM are provided by the PHI motherboard. The ADC128S102 requires an analog power supply (VA) and a digital power supply (VD). The analog power supply is set at 5.5 V and is regulated down to 5.3 V using the TPS7A4700. From there, the REF6050 is used to set VA to 5 V. The ADC128S102 uses VA as the reference as well, which defines the analog full scale of the ADC. The EVM has a provision for an external VA. To use an external analog power supply, remove R42 at the REF5060 output, which disconnects the VA supplied by the EVM. Using jumper J27, which is unpopulated by default, an external supply can be connected. There are also footprints available for a decoupling capacitor and a protective diode that must be populated if an external supply is used.

The digital supply VD is set to 3.3 V and is supplied directly from the PHI motherboard.