Title :
An All-Digital Fast-Locking Programmable DLL-Based Clock Generator
Author :
Liang, Chuan-Kang ; Yang, Rong-Jyi ; Liu, Shen-Iuan
Author_Institution :
Nat. Taiwan Univ., Taipei
Abstract :
An all-digital fast-locking programmable DLL-based clock generator is presented. By resetting the output clock every two input clock periods, the initial minimal delay constraint in the conventional architecture is eliminated. Compared with the previous work, the short locking time is also achieved. The proposed circuit has been fabricated in 0.35-mum CMOS process and occupies the active area of 0.216 mm2. The clock multiplication ratio is programmed from 2 to 15. The frequency ranges of the input and output clocks are 4 ~ 200 MHz and 60 ~ 450 MHz, respectively. It dissipates less than 17 mW at all operating frequencies from a 3.3-V supply.
Keywords :
CMOS digital integrated circuits; clocks; delay lock loops; frequency multipliers; frequency synthesizers; jitter; programmable circuits; CMOS fabrication process; all-digital delay-locked loop; all-digital fast-locking programmable DLL; clock generator; clock multiplication ratio; frequency 4 MHz to 200 MHz; frequency 60 MHz to 450 MHz; frequency synthesizer; minimal delay constraint; short locking time; size 0.35 mum; voltage 3.3 V; All-digital DLL; All-digital delay-locked loop (DLL); clock generator; clock multiplier; fast-locking; frequency synthesizer;
Journal_Title :
Circuits and Systems I: Regular Papers, IEEE Transactions on
DOI :
10.1109/TCSI.2007.913612