SYSTEMS AND ARRANGEMENTS FOR A PHASE FREQUENCY DETECTOR

摘要

A high speed, low jitter phase locked loop (PLL) with feed forward phase frequency detection is disclosed. The phase frequency detector can include a phase difference sensor providing an output signal indicating a phase difference duration between a rising edge of a reference signal and a rising edge of a feedback signal. The apparatus can also include a lead lag sensor to provide an out put signal indicating when the reference signal leads the feedback signal. In addition, a steering logic module can be coupled to the output of the phase difference sensor and the lead lag sensor and the steering logic module can steer the phase difference duration signal to a first output when the reference signal leads the feedback signal, and can steer the phase difference signal to a second output when the reference signal lags the feedback signal.