I have a few questions regarding the ADF5355 PLL IC. We intend to use it on two different cards where in both instances the desired output frequency will be between 400 – 6500 MHz.
- Since RFOUTB is not used, should the pin be terminated to ground or left floating. Bit DB10 will be set to 1 to disable output per page 27. If left floating, is a dc blocking cap recommended to prevent part damage from stray feedback? If grounded, does a 50Ω need to be included since RFOUTB is internally matched to 50Ω impedance?
- Page 35 indicates when a single-ended output is desired, a balun may be used in lieu of simply terminating RFoutA-. How would this affect the performance and quality of the output signal?
- Does ADI have a recommended part that will cover the operational range above? Is there an application circuit available for said configuration?