12-23 October 2020
GMT timezone

The Analog Front-end for the LGAD Based Precision Timing Application in CMS ETL

12 Oct 2020, 16:20
Mini Oral and Poster Front End Electronics and Fast Digitizers Poster session A-01


The analog front-end for the Low Gain Avalanche Detector (LGAD) based precision timing application in the CMS Endcap Timing Layer (ETL) has been prototyped in a 65 nm CMOS mini-ASIC named ETROC0. Serving as the very first prototype of ETL readout chip (ETROC), ETROC0 aims to study and demonstrate the performance of the analog front-end, with the goal to achieve 40 to 50 ps time resolution per hit with LGAD (therefore reach about 30ps per track with two detector-layer hits per track). ETROC0 consists of preamplifier and discriminator stages, which amplifies the LGAD signal and generates digital pulses containing time of arrival (TOA) and time over threshold (TOT) information. The actual TOA and TOT measurements will be done with a time-to-digital converter (TDC) downstream and is not part of the ETROC0. ETROC0 chips have been tested extensively using charge injection, laser, cosmic rays as well as beam, and the measured performance agrees well with simulation. The initial beam test at Fermilab has demonstrated time resolution of around 33 ps from the preamplifier waveform analysis and around 42 ps from the discriminator pulses analysis. A subset of ETROC0 chips have also been tested to a total ionizing dose (TID) of 100 MRad using X-ray machine at CERN and no performance degradation been observed. The ETROC0 design is successful and is directly used without modification for the next prototype chip, ETROC1, which has 5x5 pixel arrays and includes a new TDC stage and H-tree style clock distribution.

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Minioral Yes
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DOGRA, Sunil Manohar (Kyungpook National University (KR)) Mr EDWARDS, Christopher (Fermi National Accelerator Laboratory) GONG, Datao (Southern Methodist Univeristy) GRAY, Lindsey (Fermi National Accelerator Lab. (US)) HUANG, Xing (Central China Normal University) JOSHI, Siddhartha (Northwestern University) LEE, Jongho (Kyungpook National University (KR)) LIU, Chonghan (Southern Methodist University) LIU, Tiankuan (Southern Methodist University (US)) LOS, Sergey (FNAL) MOON, Chang-Seong (Kyungpook National University (KR)) OH, Geonhee (University of Illinois at Chicago (US)) OLSEN, Jamieson (Fermi National Accelerator Lab. (US)) RISTORI, Luciano Frances (Fermi National Accelerator Lab. (US)) SUN, Hanhan (Southern Methodist University) WANG, Xiao (University of Illinois at Chicago (US)) WU, Jinyuan (Fermi National Accelerator Lab. (US)) YE, Jingbo (Southern Methodist University, Department of Physics) YE, Zhenyu (University of Illinois at Chicago) ZHANG, Li ZHANG, Wei (Southern Methodist University) LIU, Tiehui Ted (Fermi National Accelerator Lab. (US))

Presentation materials