RC_Charge Pump Application Note AN120 Mar 19, 1998 The RC Charge Pump: A Versatile RF Library circuit for Phase Locked Loops (PLL) and Beyond. Logic gate delays and a diode amplitude demodulator are also possible with this charge-pump Stephen H. Kratzet, ELANIX, Inc. Phase-Locked Loop The RC Charge Pump token (Figure 1) in the RF library is a versatile token that can satisfy many design tasks. The charge pump is most often used as the loop filter in a phase locked loop (PLL). For detailed information on PLL simulation in SystemView please refer to application notes AN104 and AN105. The simplified PLL system in AN105 has been simplified even further for use as a reference system in this application note. This reference system uses an op-amp differential filter to close the loop. The resulting settlin……