Right now I'm trying to design a PCB for AD1955, using only 2 layers, because I want to etch the board at home.
I know I won't be able to make a perfect layout with 2 layers, but ordering a 4 layer PCB is not possible for me right now.
Bottom layer is a ground plane and all of the elements are on the top layer. Because I didn't want to use too many jumpers, I've decided to put analog stage on a separate board with independent +/-15V PSU and connect it to DAC PCB using cables.
So.. I wanted to ask for some guidelines, how to desing a DAC board with only 2 layers. Should I make +/-15V planes on the top layer, or maybe another ground plane to add some shielding? Also, is placing DAC and analog stage on separate boards a bad idea? I can upload some pictures/EAGLE files showing my ideas for the layout.
- Should the 100pF capacitor (between IOUT+/IOUT-) should be close to AD1955 or op-amps?
- Does the quality of 2.7nF/5.6nF capacitors (single-ended output from DS) affects performance, or I can freely use standard 0805 X7R capacitors?
That would be all for now.
I'll be grateful for any kind of help or suggestions