I'm not sure exactly what you are asking. Am I absolutely sure about what? Perhaps rephrase it .

However, the construction of entire has to do with generating a clock signal. So the question is whether the PLL is required to generate a clock signal. My understanding is that the purpose of the PLL is to aid in that synchronization process that takes place for external communication.

One way to look at the required question is whether PLL is the only means by which synchonization can take place? Or is PLL simply the best way of available options?

If I were the ALJ, that is the way I would be looking at it.

Opty