CY22393 Clock Behavior without Input

Question: What is the behavior of the PLL based clock outputs in case of an unlock condition of the source PLL?



If the Xtalin pin is floating, the PLLs will run off and run as high as possible and the clock outputs will be running at divided down frequencies of the PLL. If Xtalin is driven high or low and not oscillating, the outputs will be stuck high or low and will not be oscillating. We have our Crystal Oscillator application note that you may find useful for more information.