S-Space College of Engineering/Engineering Practice School (공과대학/대학원) Dept. of Electrical and Computer Engineering (전기·정보공학부) Theses (Ph.D. / Sc.D._전기·정보공학부)
Design of Injection-Locked PLL with Digital Calibration of Frequency Error and Path Mismatch
주파수 오류 및 패쓰 미스매치의 디지털 보정 회로를 포함한 주입 고정 위상 동기화 루프의 설계
- 공과대학 전기·컴퓨터공학부
- Issue Date
- 서울대학교 대학원
- Charge-stored complementary switch; frequency synthesizer; injection-locked oscillator; phase-locked loop
- 학위논문 (박사)-- 서울대학교 대학원 : 전기·컴퓨터공학부, 2017. 2. 정덕균.
- A novel injection technique for the extension of the noise-filtering band-width is proposed to filter out an oscillator’s noise in high frequency region. In addition, injection-locked phase-locked loops (IL-PLL) are proposed to mini-mize a frequency error fERR and a path mismatch pERR. Here, fERR is defined as the frequency difference between the free-running frequency of an oscillator and the desired frequency. Besides, pERR includes a non-ideal delay and a de-vice mismatch. This thesis insists two IL-PLLs using different calibration loops.
First, an IL-PLL using a charge-stored complementary switch (CSCS) injec-tion technique is proposed. The IL-PLL exhibits a wider locking range com-pared to other conventional IL-PLLs, owing to the improvement of the injection effect by the proposed CSCS. A frequency error calibration loop and a device mismatch calibration loop force the frequency error to be zero to minimize jit-ter and reference spur. The prototype chip fabricated in 65-nm CMOS technol-ogy achieves a 285-fsrms integrated jitter at 3.328 GHz from the reference clock of 52 MHz while consuming 7.16 mW. The figure-of-merit of the IL-PLL is −242.4 dB.
Second, an IL-PLL offering an excellent spur level with a time-division dual calibration (TDDC) scheme is proposed. The TDDC employs a replica delay cell in the injection-locked oscillator to detect and eliminate both a frequency error and a path mismatch. Robustness of the TDDC is verified over multiple samples by varying the supply voltage. With the TDDC enabled, the prototype chip fabricated in 65-nm CMOS technology achieves the spur reduction of 23 dBc, resulting in the spur level of -65 dBc. The integrated jitter at 2.5 GHz from the reference clock of 156.25 MHz is 198 fsrms while consuming 13.5 mW from a 1.1 V supply. The figure-of-merit of the IL-PLL is ‒242.8 dB.