Answer 2—The rising edges of the three output pulses generated in each 13-state sequence aren’t evenly spaced. Instead, they occur at integer multiples of the input clock period. The displacement in time from their ideal positions constitutes jitter in the output clock. This displacement is never greater than 2/3 of one input clock period, or 41.7 ns. In fact, the peak-to-peak jitter is exactly equal to this value.

Given that that the output clock will be divided by a minimum factor of 16 to generate timing for a 230.4-kbps serial signal, the jitter component represents just 0.96% of a single bit time, which is negligible.

Contributor: David Tweed