Through improving the phase frequency discriminator circuit structure ,and adding a control module to control charge pump current ,a charge pump phase-locked loop circuit which has the characteristics of fast-lock and wide band has been designed .When the phase error value of the phase frequency discriminator is greater than the delay timeτ of the control module ,the control switch is opened to increase the charge pump current ,the loop bandwidth is increased ,at the same time the resistance of the loop filter is reduced ,realized fast lock ,l...
