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oai:www.ideals.illinois.edu:2142/108103 2023-07-11 col_2142_5131 col_2142_8888 com_2142_5130 com_2142_8887 com_2142_234

Hanumolu, Pavan K Hanumolu, Pavan K Shanbhag, Naresh R Schutt-Aine, Jose E Zhou, Jin Megawer, Karim M. 2020-08-26T23:51:27Z 2020-08-26T23:51:27Z 2022-08-26T23:58:55Z 2020-04-13 2020-05 Low-noise high-frequency fast-startup reference frequency generators are needed in high-performance power-efficient communication systems. Frequency synthesizers that generate high-frequency clocks in modern wireline/wireless transceivers require high-frequency reference clocks to achieve excellent noise performance. In the first part of this work, we present ways to generate such reference clocks at 4 times the frequency of a standard crystal oscillator (XO) output frequency. Using extensive digital correction techniques, a 216MHz reference clock with an integrated jitter of 77fsrms is generated from a 54MHz Pierce XO. A ring oscillator based injection locking clock multiplier driven by the proposed quadrupler is used to demonstrate the efficacy of the quadrupler. Fabricated in a 65nm CMOS process, the proposed clock multiplier occupies an active area of 0.16mm2 and achieves 366fsrms integrated jitter at 4.752GHz output frequency while consuming 6.5mW power from a 1.0V supply of which 1.5mW is consumed in the quadrupler. Heavily duty-cycled communication systems that implement aggressive dynamic power management schemes to reduce average power consumption require fast-startup reference clocks which demand fast-startup crystal oscillators. In the second part of this thesis, we present ways to improve the startup time of crystal oscillators. Using a two-step injection technique in a three-step process, the proposed technique reduces the crystal oscillator startup time to within 1.5x the theoretical minimum. By solving the differential equation governing a crystal resonator under injection for arbitrary injection frequency, the behavior of energy buildup inside a crystal resonator is analyzed and used to determine optimum injection time as a function of the desired crystal oscillator steady-state amplitude and injection frequency error. Bounds on tolerable injection frequency error to guarantee the existence of optimal timing are provided. Fabricated in a 65nm CMOS process, the proposed 54MHz fast-startup crystal oscillator occupies an active area of 0.075mm2 and achieves a startup time of less than 20us across a temperature range of -40oC to 85oC while consuming a startup energy of 34.9nJ and operating from a 1.0V supply. Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2022-05-01 The student, Karim Megawer, accepted the attached license on 2020-04-10 at 14:11. The student, Karim Megawer, submitted this Dissertation for approval on 2020-04-10 at 14:35. This Dissertation was approved for publication on 2020-04-13 at 10:25. DSpace SAF Submission Ingestion Package generated from Vireo submission #14955 on 2020-08-25 at 17:27:15 Made available in DSpace on 2020-08-26T23:51:27Z (GMT). No. of bitstreams: 7 MEGAWER-DISSERTATION-2020.pdf: 5390393 bytes, checksum: 1d2d82abda73df10b3c928895b399382 (MD5) ISSCC 2018.pdf: 130062 bytes, checksum: 142ad5133aca98266f5802f840ac9ce8 (MD5) ISSCC 2019.pdf: 130604 bytes, checksum: 73d187b72c3e5229f55026164e813c04 (MD5) JSSC 2018.pdf: 129165 bytes, checksum: ac80e32401550f4173d2dee888ea4bad (MD5) JSSC 2019.pdf: 128731 bytes, checksum: c1ffb11f932f76ff29c72ac4afdf0a96 (MD5) LICENSE.txt: 4210 bytes, checksum: 2245877475f79267be8db9059c516f43 (MD5) PROQUEST_LICENSE.txt: 4556 bytes, checksum: b1469d9a726b807b388c722fac227043 (MD5) Previous issue date: 2020-04-13 Embargo set by: Seth Robbins for item 115712 Lift date: 2022-08-26T23:51:32Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 115712 Lift date: 2022-08-26T23:54:40Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 115712 Lift date: 2022-08-26T23:55:59Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 115712 Lift date: 2022-08-26T23:57:28Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 115712 Lift date: 2022-08-26T23:58:55Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system U of I Only application/pdf http://hdl.handle.net/2142/108103 en Copyright 2020 Karim M. Megawer Crystal oscillator (XO) digitally controlled oscillator (DCO) duty-cycle correction frequency quadrupler injection-locked clock multiplier (ILCM) jitter least mean square (LMS) ring oscillator (RO) startup time High-performance reference frequency generation techniques text Thesis Electrical & Computer Eng Electrical & Computer Engr University of Illinois at Urbana-Champaign Dissertation Ph.D.