5 Power Supplies

The power supply section on the EVM provides flexibility to power the device using the onboard regulator(s) or direct supply input(s). A combination of 0-Ω resistor options allows the user to modify the EVM power supply configuration, if desired.

By default, 3.3 V is supplied to VDD and VDDR input through the onboard LDO regulator, U6. To power the regulator, connect a 3.3-V to 5-V input voltage and ground from an external power source to the terminal block, J3.

To modify the EVM with a different power supply configuration, populate the resistor options as shown in Table 5-1. Then, apply the appropriate voltage(s) to the EVM power input(s).

If the EVM is configured for dual direct supplies, connect a 3.3-V supply to both VDD and VDDR supply and associated ground to the labeled terminal blocks.

Decoupling capacitors and 0-Ω resistor footprints, which can accommodate ferrite beads, can be used to isolate the EVM power input(s) from the device power pins.