Title :
A Time-Constant Calibrated Phase-Locked Loop With a Fast-Locked Time
Author :
Han, Sung-Rung ; Chuang, Chi-Nan ; Liu, Shen-Iuan
Author_Institution :
Dept. of Electr. Eng., Nat. Taiwan Univ., Taipei
Abstract :
A time-constant calibrated phase-locked loop with a fast-locked time is presented. A variable capacitance multiplier (VCM) is developed to adjust the equivalent capacitance in the loop filter. And a calibration circuit is used to allow the time constant of the loop filter to track with the reference clock. By using the proposed time-constant calibration circuit and the VCM, the fast acquisition time is achieved and the loop capacitance is also multiplied. A prototype has been fabricated in a 0.35-mum CMOS process to demonstrate the proposed circuit
Keywords :
CMOS integrated circuits; calibration; multiplying circuits; phase locked loops; reference circuits; 0.35 micron; CMOS process; calibration circuit; equivalent capacitance; fast-locked time; loop capacitance; loop filter; reference clock; time-constant calibrated phase-locked loop; variable capacitance multiplier; Calibration; Capacitance; Charge pumps; Circuits; Clocks; Damping; Filters; Frequency; Phase locked loops; Temperature; Fast locked; phase-locked loop (PLL); time-constant calibration; variable capacitance multiplier (VCM);
Journal_Title :
Circuits and Systems II: Express Briefs, IEEE Transactions on
DOI :
10.1109/TCSII.2006.883826
