Portable devices need to be able to communicate with the outside world via many different networks/channels/frequencies. But doing so requires wide band capability. The answer is a 336 implementation. The alternative would be either limited communication possiblilities or bulky and expensive hardware to address all types.

My understanding of how this operates is to sample the communication stream to figure out which communication standard is the best fit and once that is determined digitally force a correction to arrive at a predetermined frequency which is then used to read the communications stream.

In this particular application I believe the reference signal does is coming from something other than the external crystal. When sampling the communications stream to determine the commuinications standard being used, the PLL needs to have a wide operating range. So it runs freely during this sampling stage afterwhich software programming kicks in to digitally correct to the communication standard that was determined from the sampling phase.

That is a summary of my understanding in simple terms, and I may not have got it completely right. Obviously it's more complicated than that. But this wide band capability is what TI will be asked to testify about.

Opty