Quick question on the FX3 USB3014 chip and the phase noise requirements. On one of the App notes Cypress recommends using the ASEMB-19.200MHz-LY oscillator. I wanted to run the FX3 at 26MHz so I asked Abracon about using the ASEMB-26.00MHz-LY oscillator and sent them the phase noise requirements outlined in the FX3 datasheet. They returned the phase noise of the ASEMB-26.00MHz-LY and it does not meet the requirements outlined in the FX3 datasheet. They did recommend the following oscillator which does meet the phase noise requirements Abracon - ASTMUPCE-33-26.000MHz-LJ-E-T but the only difference is this oscillator has a stability of +/-20ppm while the ASEMB is +/-10ppm.
What is the requirement on the Frequency Stability of the oscillator?
The maximum frequency deviation allowed for a clock input to FX3 is 150 ppm ( Refer to Table 4. FX3 Input Clock Specifications in FX3 datasheet).