I've designed by own board based around the ADAU1701. I've followed the datasheet as best as I could down to a T and used a tight layout with best practices. I seem to be stuck at the most basic issue - generating a clock signal. From my research I should be seeing around 2V swing at MCLKi. However I am only seeing a steady DC voltage of 1V at MCLKi. On OSCO, I see a 12.288mhz sine wave 1V Peak to Peak (between 1V and 2V). I tried swapping out the ADAU1701 but it's the same thing. Crystal is an HC49-S at 12.288 MHz with 18pf load capacitors, and a 100 ohm damping resistor. I've been over the layout and design over and over and can't find anything wrong.
My question is, for those with eval boards or your own designs, what are you seeing in terms of voltage swings at these two pins? Is MCLKi perhaps current driven in this configuration? I have nothing to compare to.
Thanks in advance for any advice.
[edited by: djamps at 5:59 PM (GMT -4) on 11 Jun 2021]