Broadband multi-phase output delay locked loop circuit utilizing a delay matrix

Abstract

A broadband multi-phase output delay locked loop (DLL) circuit can be operated in a wide range of frequencies and generate various phases. Unlike conventional voltage control delay lines in which delay cells are connected in series, the DLL circuit utilizes a delay matrix in which a resistant network is used so that the number of delay cells connected in series is reduced, various phases can be outputted, and a delay interval error (phase error) due to the resistant network is minimized. The current of the delay cells is controlled so that the delay cells in the delay matrix can operate in a wide range of frequencies, and load capacitance values of capacitors connected in parallel in the delay cells can be controlled.