Development of a DAQ front-end board for X-ray free-electron laser experiments

In this study, we developed a new data acquisition (DAQ) front-end board for X-ray free-electron laser (XFEL) experiments. X-ray imaging detectors are indispensable for X-ray experiments and their performance is being continuously enhanced. Moreover, recently performed experiments have used various types of detectors. Therefore, we propose a DAQ front-end system design that satisfies relatively high data rates and supports a variety of X-ray imaging detector interfaces. The novel detector that is under development at SPring-8 was selected for one of its applications. Because the first phase of the detector adopted a camera link (CL) interface, we developed a DAQ front-end with a CL field-programmable gate array mezzanine card (FMC). The proposed design has a general-purpose input/output interface to receive trigger signals and event-building information for synchronization of equipments. Moreover, bit error checking during data transmission via CL was also implemented. The system was evaluated for operation tests lasting 209 h with a 3.7 Gbps bandwidth. The results showed that the system achieved stable operation, and no errors were found during bitwise checks or with trigger and event-building information processes. The results indicated that using the silicon-on-insulator photon imaging array sensor (SOPHIAS), the DAQ front-end board was sufficiently stable for XFEL experiments.