Power supply design for your final product need not be extraordinary,but do note that the quality of your supply will directly affect the ADC performance.
From the experience I have of designing a few PSoC3 boards,an ordinary L1117-3.3V type volrage regulator in its typical configuration will serve you well for ADC designs upto 16 bits or so,depending on your board layout.
You could also consider powering your board from a voltage reference.Check out the schematics for the CY8CKIT-030 particularly to get an idea of a good analog oriented power supply.
I have designed my own PCB with a LM117-3.3 V and hhad pretty ood results on the ADC. As long as you have the right capacitors on the VCCA/VCCD, VDDIO pins you should be good. You can reuse the scematic provided with CY8CKit-030 to quickly get going. Howere to understand the requirements on power supply in detial, you can refer the app noted mentioned above.