{"title":"0.41-pJ/b/dB Asymmetric Simultaneous Bidirectional Transceivers With PAM-4 Forward and PAM-2 Back Channels for 5-m Automotive Camera Link","authors":"Yunhee Lee, Woonghee Lee, Minkyo Shim, Soyeong Shin, Woo-Seok Choi, D. Jeong","doi":"10.1109/vlsitechnologyandcir46769.2022.9830299","DOIUrl":null,"url":null,"abstract":"This paper presents asymmetric simultaneous bidirectional (SBD) transceivers for the next-generation automotive camera link. To realize the SBD operation with the PAM-4 signaling, the proposed wide linear range (WLR) hybrid excludes the voltage-dependent non-linear transconductance (gm) of active elements. A two-step hybrid strategy suppressing the PAM-4 forward channel (FC), including the FFE, is utilized for low power and design simplicity. A Σα hybrid removes only four primary DC levels, and 2nd order gm-capacitor (gmC) low-pass filter (LPF) filters out residual/echoes from the hybrid/channel. An echo canceller (EC) technique is also employed to further reduce the reflections of the PAM-2 back channel (BC). The highly asymmetric SBD transceivers with 12-Gb/s PAM-4 FC and 125-Mb/s PAM-2 BC achieve BER<10-12 over 5-m cable (15.9 dB loss). Prototype chips fabricated in 40-nm technology consume 78.4 mW, exhibiting an FoM of 0.41 pJ/b/dB.","PeriodicalId":332454,"journal":{"name":"2022 IEEE Symposium on VLSI Technology and Circuits (VLSI Technology and Circuits)","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2022-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"4","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"2022 IEEE Symposium on VLSI Technology and Circuits (VLSI Technology and Circuits)","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/vlsitechnologyandcir46769.2022.9830299","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 4
Abstract
This paper presents asymmetric simultaneous bidirectional (SBD) transceivers for the next-generation automotive camera link. To realize the SBD operation with the PAM-4 signaling, the proposed wide linear range (WLR) hybrid excludes the voltage-dependent non-linear transconductance (gm) of active elements. A two-step hybrid strategy suppressing the PAM-4 forward channel (FC), including the FFE, is utilized for low power and design simplicity. A Σα hybrid removes only four primary DC levels, and 2nd order gm-capacitor (gmC) low-pass filter (LPF) filters out residual/echoes from the hybrid/channel. An echo canceller (EC) technique is also employed to further reduce the reflections of the PAM-2 back channel (BC). The highly asymmetric SBD transceivers with 12-Gb/s PAM-4 FC and 125-Mb/s PAM-2 BC achieve BER<10-12 over 5-m cable (15.9 dB loss). Prototype chips fabricated in 40-nm technology consume 78.4 mW, exhibiting an FoM of 0.41 pJ/b/dB.