Dear Connor,
Thank-you for your second update.
I am trying to reply to your email but the return email address is a 'no-reply' address. How can I email you without my email bouncing back?
Hi Deryck,
I'm not sure about the problem with the email, but usually I just respond directly on the E2E forum instead of through email. I wanted to correct one of my previous comments from the other thread: "1. R16 and R17 XO_CAPCTRL_BY1: These should be reset to the default values of 0x0 for R16 and 0x80 for R17. It's possible that it's pulling the XO frequency too far and making it difficult for the PLL to lock correctly." I actually did some testing with the EVM and didn't notice any issues with your configuration for R16 and R17.
I reviewed your schematic and it looks like there are 50 Ohm resistors to ground (resistors R19 and R20). For LVPECL, 150 Ohm should be used to drive the proper swing, but I would still expect to see some output. I've attached a picture of the recommended termination scheme from the LMK61E2 EVM for reference. How are you measuring the signal? Also, have you confirmed that the PLL is locked by reading the value in registers R66 and R72?
Regards,
Connor
