2 Power Supply

The PCM182xEVM/PCM182xQ1EVM can be powered with a single 5-V power supply connected to J6. Onboard low dropout regulators convert the 5-V supply to the 3.3-V and 1.8-V rails used by the ADC. The analog supply, AVDD, is fixed at 3.3 V. The digital supply, IOVDD, can be set to either 1.8 V or 3.3 V with J5. It is also possible to power the ADC directly by removing J9 and J5 and applying a voltage directly to the AVDD and IOVDD test points. Note that if this is done, it is important to keep J10 populated (or ensure there is a path between the pins if the supply current is being monitored) as this jumper connects the applied IOVDD to the mode selection pins and other circuitry that relies on IOVDD.