Patent ID: 6989699

Claim:
A circuit for phase detection, comprising: a phase detector including a first input for receiving a first input signal having a first phase angle, and a second input for receiving a second input signal having a second phase angle, said phase detector having first and second outputs; first and second current sources, the first current source including a reference current input; first and second reference current sources; a first switch coupled to the reference current input of the first current source and also coupled to the first or second reference current sources, said first switch for coupling the reference current input of the first current source to one of the first and second reference current sources, wherein a current associated with the first current source always maintains a nonzero value during operation of the phase detection circuit, the first switch having a control input connected to the first output of the phase detector; a second switch coupled to the second current source for connecting and disconnecting the second current source to and from a predetermined node, the second switch having a control input connected to the second output of the phase detector; and a signal output coupled to the first and second current sources for providing an output current based on a phase deviation between the first and second phase angles.