摘要

A digital phase-locked loop (DPLL) employs noise cancellation to mitigate performance degradation due to noise on the ring oscillator supply voltage. A deterministic test signal-based digital background calibration is used to accurately set the cancellation gain and thus achieve accurate cancellation under different process, voltage, temperature, and operating frequency conditions. A hybrid, linear proportional control and bang-bang digital integral control, is used to obviate the need for a high-resolution time-to-digital converter and reduce jitter due to frequency quantization error. Fabricated in 0.13 mu m CMOS technology, the DPLL operates from a 1.0 V supply and achieves an operating range of 0.4-to-3 GHz. At 1.5 GHz, the DPLL consumes 2.65 mW power wherein the cancellation circuitry consumes about 280 mu W. The proposed noise cancellation scheme reduces the DPLL's peak-to-peak jitter from 330 to 50 ps in the presence of a 30 mV(pp) 10 MHz supply noise tone, and the DPLL peak-to-peak jitter is 50 ps in the absence of any supply noise. The DPLL occupies an active die area of 0.08 mm(2), of which the calibration logic and cancellation circuitry occupy only 12.5%.

  • 出版日期2011-12