Quiz: Lead/Lag Network Determine the transfer function V O (s)/V D (s) for the lead-lag network shown: VDVD VOVO 200  5000  2000  100 .01 uf VCO PD Compute DC Gain, Pole Frequency, and Zero Frequency

PLL Acquisition PLL’s may have difficulty locking on to a signal, even though, once locked, they can track it easily. For reliable acquisition, the input signal frequency should be within the range: If this condition is satisfied, the acquisition time is usually within Depending on the signal deviation rate, loop gain and PD range characteristics, the PLL may have a statistically good chance of acquiring a signal that does not meet the above characteristics. Otherwise...

Acquisition Tricks Broaden Loop bandwidth during acquisition Sweep VCO Free-running frequency during acquisition Sweep rate should be limited to May have to lower sweep rate even more if the phase noise of the input is excessive. If the S/N of the input signal is less than 10 dB, then forget it!