Tuesday, November 22, 2005

PCM4202 EVM Study

PCM4202 EVM users guide

I've been looking at this EVM to see how things are done on TI's EVM's - looking for good design guides.

100R Resistors on outputs:
It looks like there are 100 ohm resistors (in series, NOT tied to ground) on every logic device's output. This (according to MCS on Groupdiy) is for termination reasons and other factors.

Is used as a buffer/line driver for the 3.3V devices on the board.
For 5V devices

look to be good replacements, but they need to support up to 256fS (around 25MHz).

The CDC337 looks very interesting - it's a Clock driver that can support a single clock in, the 4 out, plus another 4 at half the rate. So if we take 256fS as one clock rate, we can get 128fS out as well.

More as I think of it. :)



No comments: