Wide-range (25 ns) and high-resolution (48.8 ps) clock phase shifter

A wide-range (25 ns), high-resolution (48.8 ps) clock phase shifter developed and fabricated using a 0.13 μm CMOS technology is presented. To achieve both wide range and high resolution with good linearity while minimising area and power consumption, a coarse-fine two-step phase-shifting structure is proposed. A delay-locked loop with an unconventional clock input setup is used in the fine-shifting stage to ahieve the high resolution. Test results show that the standard deviations of the differential nonlinearity and integral nonlinearity are 4.7 ps and 4.3 ps, respectively.