# Powering ETH Controllers

I began working with Ethernet controllers and there is a recurring theme that keeps confusing me.

Currently I am incorporating the KSZ9031RNX into my design. The data sheet calls for digital and analog voltage supplies. My first thought is that I will need to incorporate a DAC in my PM circuitry.

However, when looking at the reference design for said chip, I notice that both supplies come from the same DC source, only to be separated by a FB. So does this mean the IC is taking care of the digital to analog conversion? I am just trying to understand this so I can move on.Thanks in advance.

• i think that the datasheet is referring to separate power supplies for the analog and the digital sections ... it is not talking about a D/A converter .... the D & A means D and A – jsotola Aug 30 '19 at 17:01
• Yes exactly. However, the reference design shows that both of these supplies come from a DC input. – circuit_noob533 Aug 30 '19 at 17:14