Phase locked loop circuit, electronic device including a phase locked loop circuit and method for generating a periodic signal

摘要

A phase locked loop (PLL) circuit ( 1 ) comprising a loop input (11); a phase detector section ( 2 ) for detecting a phase difference between an input signal and a reference signal. The phase detector section ( 2 ) has a detector input connected to the loop input, a reference input and a detector output for outputting a signal related to the phase difference. A controlled oscillator ( 4 ) is connected with an input to the detector output and an oscillator output is connected to a loop output ( 12 ). The PLL has a feedback circuit which connects the oscillator output to the reference input, wherein the feedback circuit includes a device ( 7;71 - 74 ) having a transfer function with at least one zero.