Differential multi-phase DLL for reconfigurable radio frequency synthesizer

A multiphase, delay-locked loop (DLL) based frequency synthesizer is designed for harmonic rejection mixing in reconfigurable radios. This frequency synthesizer uses a 1 GHz input reference frequency, and achieves ≤ 20ns settling time by utilizing a wide loop bandwidth. The circuit has been designed in 0.13-μm CMOS technology. It is designed for a frequency range of 500 MHz to 3 GHz with stuck/harmonic lock removal assist.