Using the ADF4360-8 in a FM modulation scenario generating a VHF carrier with an audio signal tied into the VTUNE pin. Loop filter is configured with a cutoff frequency of 100Hz to allow the audio to pass through the PLL.
As the FM deviation is increased above 20kHz, the harmonics in the received demodulated audio increases which is a concern for our application. Desired FM deviation is 75kHz but based on measurement need to keep FM deviation below 20kHz to manage harmonic levels.
Looking for more information on the Internal Compensation network as the harmonic content is present on the CC pin. Currently using the suggested decoupling (CC = 10nF and CN = 10uF) but there is limited info on the what the internal compensation consists of and any possibility of optimization with these pins.
