question about power supply

[sean]

I need to design a 3.3v PCI board with an ad9042(3.3v analog and 3.3 digital) and a tms320c6416(3.3v digital).How could I handle the power problem?
Can anybody give me any advice?

[Carl_at_xrite]

You'll need to have a split plane for both 3.3v and grounds.
You'll probably also want to filter your 3.3v digital by placing a 10 ohm series resistor from 3.3v to 3.3a if you don't have a independant supply and then place some filter caps on both sides of the resistor.
Carl

[sean]

It seems so simple,but I think digital power is not isolated from analog power.Could you recommend me a chip which can isolate different power?Or other suggestion?

[rkv]

Analog supply(3.3va) can be derived by filtering digital supply(3.3v). This is the common practice for adc. You can use passive RLC circuit for filtering. Really if you want to isolate analog supply from digital supply then use isolated DC-DC converter.

RKV