학술논문

A 60-Gb/s 1.2-pJ/bit 1/4-Rate PAM-4 Receiver With a Jitter Compensation CDR
Document Type
Periodical
Source
IEEE Journal of Solid-State Circuits IEEE J. Solid-State Circuits Solid-State Circuits, IEEE Journal of. 59(2):449-463 Feb, 2024
Subject
Components, Circuits, Devices and Systems
Engineered Materials, Dielectrics and Plasmas
Computing and Processing
Jitter
Clocks
Bandwidth
Voltage
Phase locked loops
Optical filters
Low-pass filters
Clock and data recovery (CDR)
decoupled jitter transfer (JTRAN) and jitter tolerance (JTOL)
four-level pulse amplitude modulation (PAM-4)
jitter compensation
source synchronous
uncorrelated jitter
Language
ISSN
0018-9200
1558-173X
Abstract
This article presents a four-level pulse amplitude modulation (PAM-4) receiver (Rx) with a jitter compensation clock and data recovery (JCCDR) for high-speed retimer application. The JCCDR can attenuate the jitter transfer (JTRAN) from the input PAM-4 signal to the recovered clock and data without sacrificing the jitter tolerance (JTOL) bandwidth. A jitter compensation circuit (JCC) is implemented within the JCCDR to support JTRAN detection, complementary signal generation, and JTRAN attenuation functions. Theoretical analysis is performed to verify the effectiveness and challenges of the proposed method. Prototyped in 40-nm CMOS, the Rx achieves error-free operation with PAM-4 input from 30 to 60 Gb/s. The JCCDR provides an ultralow $< -$ 8 dB JTRAN while maintaining a 40-MHz wide JTOL bandwidth with a 0.2-UIPP jitter amplitude. A jitter compensation ratio up to 60% can be supported from dc to 4 MHz.