Title :
A low-jitter multiphase digital delay-locked loop for nuclear instruments and biomedical imaging applications
Author :
Gao, Wu ; Gao, Deyuan ; Hu-Guo, Christine ; Wei, Tingcun ; Hu, Yann
Author_Institution :
Sch. of Comput. Sci. & Technol., Northwestern Polytech. Univ., Xi´´an, China
Abstract :
This paper presents a novel digital delay-locked loop (DDLL) dedicated to generate multiphase delayed clocks for the development of the multi-channel analog-to-digital converters (ADCs) and/or time-to-digital converters (TDCs). The DDLL consists of a digital delay chain using linear delay elements, a Bangbang phase detector, a Up/Down counter and a digital filter. The digital filter is utilized to reduce digital ripples when DDLL is locked. A prototype chip of the proposed DDLL with 32 delay cells is designed and fabricated in AMS 0.35 μm CMOS process. The die area is 690 μm × 73 μm. For the DDLL core, the rms jitter and the peak-to-peak jitter of is 0 and 19.8 ps at 50 MHz clock. However, jitter-tolerant performances can be achieved when the DDLL core and the digital filter are used as a multiphase clock generator. The total power dissipation is about 3 mW.
Keywords :
CMOS integrated circuits; analogue-digital conversion; biomedical imaging; delay lock loops; jitter; nuclear instrumentation; ADC; CMOS process; DDLL; TDC; bangbang phase detector; biomedical imaging; digital filter; frequency 50 MHz; linear delay element; low-jitter multiphase digital delay-locked loop; multichannel analog-to-digital converter; multiphase clock generator; nuclear instrument; peak-to-peak jitter; power 3 mW; rms jitter; size 0.35 micron; time-to-digital converter; up/down counter; Analog-digital conversion; Biomedical imaging; Clocks; Counting circuits; Delay lines; Detectors; Digital filters; Jitter; Nuclear power generation; Phase detection;
Conference_Titel :
Industrial Electronics and Applications (ICIEA), 2010 the 5th IEEE Conference on
Conference_Location :
Taichung
Print_ISBN :
978-1-4244-5045-9
Electronic_ISBN :
978-1-4244-5046-6
DOI :
10.1109/ICIEA.2010.5515257