Clock synchronization design and evaluation for trigger-less data acquisition system

Clock synchronization design and evaluation for trigger-less data acquisition system 1 2 first-author 1 2 corresp Corresponding author. E-mail address: skz@ustc.edu.cn Corresponding author. E-mail address: skz@ustc.edu.cn skz@ustc.edu.cn 1 2 State Key Laboratory of Particle Detection & Electronics, Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China State Key Laboratory of Particle Detection & Electronics, Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China Anhui Key Laboratory of Physical Electronics, Hefei 230026, China Anhui Key Laboratory of Physical Electronics, Hefei 230026, China For modern particle physics experiments, trigger-less data acquisition (DAQ) system has been put into practice because of the need of reaction multiplicity and trigger flexibility. In such new DAQ systems, global synchronized clock plays an important role because it affects the granularity of time slice and precision of reference clock. In this paper, a novel synchronized clock distribution method is proposed. With the help of modulation technique, master clock module distributes system clock to each slave module. To synchronize slave clocks, the propagation delay is adjusted and the clock phase is aligned by an FPGA chip automatically. Furthermore, an ADC- based method is proposed to evaluate the performance of multi-module clock synchronization simultaneously. The experiments of a prototype system show that slave clocks can be synchronized less than 100 ps over 150 m range. The proposed method is simple and flexible, and it can be used in trigger-less DAQ system and other applications of clock distribution preciously. Trigger-less DAQ system Clock distribution Synchronization ADC-based evaluation References Essel H G . IEEE Trans Nucl Sci , 2006 , 53 : 677 - 681 . IEEE Trans Nucl Sci Liu Z A , Gong W X , Guo Y N , et al . RTC, 2007, 4382859: Trigger system of BESIII , RTC, Fermilab , Batavia IL, USA , April 29-May 4, 2007 , 1 - 4 . RTC, 2007, 4382859: Trigger system of BESIII Konorov I , Angerer H , Mann A , et al . NSSMIC. 2009. 5402171: SODA: Time distribution system for the PANDA experiment , NSSMIC , Orlando, FL, USA , 2009 , 1863 - 1865 . NSSMIC. 2009. 5402171: SODA: Time distribution system for the PANDA experiment Alessio F , Guzik Z , Jacobsson R . RTC.2009.5321838: A 40 MHz trigger-free readout architecture for the LHCb experiment , RTC , Beijing, China , May, 2009 , 206 - 213 . RTC.2009.5321838: A 40 MHz trigger-free readout architecture for the LHCb experiment An Q , Bai Y X , Bi X J , et al . Nucl Instrum Meth Phys Res A , 2011 , 644 : 11 - 17 . Nucl Instrum Meth Phys Res A Moreira P , Serrano J , Wlostowski T , et al . ISPCS. 2009. 5340196: White Rabbit: Sub-nanosecond timing distribution over ethernet , ISPCS , Brescia, Italy , October 2009 , 1 - 5 . ISPCS. 2009. 5340196: White Rabbit: Sub-nanosecond timing distribution over ethernet Li C , Liu S B , Shang L F , et al . Nucl Sci Tech , 2012 , 23 : 230 - 236 . Nucl Sci Tech Korhonen T. Paul Scherrer Institut, Switzerland. Review of accelerator timing systems , ICALEPCS . Trieste, Italy , October, 1999 , 167 - 170 . Paul Scherrer Institut, Switzerland. Review of accelerator timing systems Li H , Liu S B , Feng C Q , et al . IEEE Trans Nucl Sci , 2006 , 57 : 442 - 445 . IEEE Trans Nucl Sci IEEE Standard for a Precision clock synchronization protocol for networked measurement and control systems , IEEE Std 1588-2002 , IEEE Instrumentation & Measurement Society , 2002 , 1 - 144 . IEEE Standard for a Precision clock synchronization protocol for networked measurement and control systems Serrano J , Alvarez P , Cattin M , et al . CERN-ATS-2009-096: The White Rabbit project , ICALEPCS , Kobe, Japan , October, 2009 . CERN-ATS-2009-096: The White Rabbit project Ding K , Zhong S C . Acta Elec Sinica , 2003 , 31 : 142 - 145 . Acta Elec Sinica Qi G Q , Jia X L . Acta Elec Sinica , 2001 , 29 : 1164 - 1167 . Acta Elec Sinica Cao Z , Liu S B , Li C , et al . Nucl Sci Tech , 2011 , 22 : 353 - 357 . Nucl Sci Tech Hao X J , Liu S B , Zhao L , et al . Nucl Sci Tech , 2011 , 22 : 178 - 184 . Nucl Sci Tech Virtex-5 FPGA Data Sheet: DC and switching characteristics, DS202 (V5.3) , May, 2010 . Virtex-5 FPGA Data Sheet: DC and switching characteristics, DS202 (V5.3) 10.13538/j.1001-8042/nst.23.361-368 Supported by the National Natural Science Foundation of China (No.11005107) and Anhui University Natural Science Research (No.KJ2010A334) 2012-05-29 2012-12-20 2021-01-19 2012 Nuclear Science and Techniques 06 23