Development of readout electronics for bunch arrival-time monitor system at SXFEL

  • Jin-Guo Wang
  • Bo LiuEmail author


A bunch arrival-time monitor (BAM) system, based on electro-optical intensity modulation scheme, is under study at Shanghai Soft X-ray Free Electron Laser. The aim of the study is to achieve high-precision time measurement for minimizing bunch fluctuations. A readout electronics is developed to fulfill the requirements of the BAM system. The readout electronics is mainly composed of a signal conditioning circuit, field-programmable gate array (FPGA), mezzanine card (FMC150), and powerful FPGA carrier board. The signal conditioning circuit converts the laser pulses into electrical pulse signals using a photodiode. Thereafter, it performs splitting and low-noise amplification to achieve the best voltage sampling performance of the dual-channel analog-to-digital converter (ADC) in FMC150. The FMC150 ADC daughter card includes a 14-bit 250 Msps dual-channel high-speed ADC, a clock configuration, and a management module. The powerful FPGA carrier board is a commercial high-performance Xilinx Kintex-7 FPGA evaluation board. To achieve clock and data alignment for ADC data capture at a high sampling rate, we used ISERDES, IDELAY, and dedicated carry-in resources in the Kintex-7 FPGA. This paper presents a detailed development of the readout electronics in the BAM system and its performance.


Bunch arrival-time monitor (BAM) Shanghai Soft X-ray Free Electron Laser (SXFEL) Field-programmable gate array (FPGA) Signal conditioning High-speed analog-to-digital converter (ADC) 


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Copyright information

© China Science Publishing & Media Ltd. (Science Press), Shanghai Institute of Applied Physics, the Chinese Academy of Sciences, Chinese Nuclear Society and Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  1. 1.Shanghai Institute of Applied PhysicsChinese Academy of ScienceShanghaiChina
  2. 2.University of the Chinese Academy of ScienceBeijingChina

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