A voltage controller oscillator (VCO) circuit is provided for use in a phase-locked loop (PLL) circuit. The VCO circuit has a VCO and a low pass filter. The VCO includes a first input that receives a first voltage control signal from an output of a PLL circuit loop filter, a second input that receives a second voltage control signal, and an output that provides a periodic output signal. The low-pass filter includes an input connected to the output of the PLL circuit loop filter, and an output connected to the second input of the VCO. The first input of the VCO provides high frequency voltage control, and the second input of the VCO provides low frequency voltage control.