If your reference frequency, connected to REFin pin, is 28.6 MHz; R counter = 1 and MUXOUT is set to R_Counter_Output, then the signal on the MUXOUT pin should be 28.6 MHz. From your screenshot, it looks to be at 205 MHz. And it looks unstable/very noisy.
Can you post a plot of your LTC6905 output connected directly to the spectrum analyzer? The spectrum analyzer should be centered at 28.6 MHz.
If your reference frequency, connected to REFin pin, is 28.6 MHz; R counter = 1 and MUXOUT is set to R_Counter_Output, then the signal on the MUXOUT pin should be 28.6 MHz. From your screenshot, it looks to be at 205 MHz. And it looks unstable/very noisy.
Can you post a plot of your LTC6905 output connected directly to the spectrum analyzer? The spectrum analyzer should be centered at 28.6 MHz.
