BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Monitoring Single Event Upsets in SRAM-based FPGAs at the SuperKEK B Interaction Point DTSTART;VALUE=DATE-TIME:20170303T032000Z DTEND;VALUE=DATE-TIME:20170303T034000Z DTSTAMP;VALUE=DATE-TIME:20260421T041735Z UID:indico-contribution-1743@indico.inp.nsk.su DESCRIPTION:Speakers: Raffaele Giordano (University of Naples and INFN)\nS tatic RAM-based Field Programmable Gate Arrays (SRAM-based FPGAs) [1\, 2] are widely adopted in Trigger and Data Acquisition (TDAQ) systems of High- Energy Physics (HEP) experiments for implementing fast logic due to their re-configurability\, large real-time processing capabilities and embedded high-speed serial IOs. However\, these devices are sensitive to radiation effects such as single event upsets (SEUs) or multiple bit upsets (MBUs) i n the configuration memory\, which may alter the functionality of the impl emented circuit. Therefore\, they are normally employed only in off-dete ctor regions\, where no radiation is present. Special families of SRAM-ba sed FPGAs (e.g. the Xilinx Virtex-5QV) have been designed for applications in radiation environments\, but their excessive cost (few 10k USD)\, with respect to their standard counterpart ($\\sim$ 500 USD)\, usually forbids their usage in many applications\, including HEP. Therefore\, there is a strong interest in finding solutions for enabling the usage of standard SR AM-based FPGAs also on-detector. Methods based on modular redundancy and periodic refresh of the configuration\, i.e. configuration scrubbing\, are used in order to mitigate single event effects\, which become more signif icant as the technological scaling proceeds towards smaller feature sizes. In fact\, latest devices also include dedicated circuitry implementing er ror correcting codes for mitigating configuration errors. The expected bit configuration upset rate is valuable information for choosing which prote ction strategy\, or which mixture of strategies\, to adopt. \nTypically\, test campaigns are carried out at dedicated irradiation facilities by mean s of heavy ions\, proton and neutron beams [3\,4\,5] and they permit to de termine the particle to bit error cross section. However\, a reliable pred iction of the upset rate\, and of radiation effects in general\, requires the knowledge of the cross section as function of the particle species and their spectra and it depends on a detailed knowledge of the radiation flu xes. Often such information is not available with sufficient precision\, a nd when possible an in situ (or in flight for space applications) measurem ent of the upset rate is highly recommended. For instance\, experiments at the Large Hadron Collider have been monitoring SEUs in readout control FP GAs [6]\, experiments in space have been launched in order to measure sing le event effects rates and compare them to predictions based on cross sect ions [7]. Furthermore\, over the last decade\, FPGA vendors have been carr ying out experiments aimed at measuring SEUs induced by atmospheric neutr ons in their devices [8].\n\nIn February 2016\, the SuperKEKB [9] $e^+e^-$ high-luminosity ($8\\cdot10^{35} cm^{-2} s^{-1}$) collider of the KEK lab oratory (Tsukuba\, Japan) started being commissioned. A dedicated commissi oning detector\, named BEAST2\, has been being used to characterize beam b ackgrounds prior to the Belle2 detector roll into the beams and to provide tuning parameters for Monte Carlo simulations. BEAST2 consists of a fiber glass support structure and several subdetectors mounted onto it\, includ ing time projection chambers (TPCs) and He-3 tubes. \n\nIn this work\, we present direct measurements of radiation-induced soft-errors on a SRAM-bas ed FPGA device installed on the BEAST2 frame at a distance of $\\sim$ 1 m from the beam interaction point. Our goal is to provide experimental resul ts of the expected FPGA configuration error rate and power consumption var iation at Belle2 and at other experiments operating in similar radiation c onditions. For this study\, we designed a dedicated board hosting a Xilin x Kintex-7 325T device without additional active components\, in such a w ay to be able to decouple FPGA failures from those of other devices. The b oard receives power and clock from dedicated remote generators installed i n a counting room. The configuration and read back are performed via a JTA G connection and they are managed by a dedicated single board computer . D uring the commissioning of the collider\, we periodically read back the FP GA configuration in order to detect errors and we logged the power consump tion on the different power domains of the device. Currents for both elect ron and positron rings spanned a range between 50 and 500 mA\, therefore p roviding data about the FPGA in different radiation conditions. Even if th e machine is not providing collisions yet\, as the beams are not focused t o the interaction point\, our results show a rate of 0.02 upsets/day avera ged over the whole commissioning time frame. BEAST2 subdetectors provided valuable information about the radiation environment.\nThis work is part o f the ROAL SIR project funded by the Italian Ministry of Research (MIUR).\ n\n\nReferences \n\n[1] Xilinx Inc.\, “Virtex UltraScale FPGAs Data Shee t: DC and AC Switching Characteristics\,” DS893 (v1.7.1) April 4\, 2016\ n\n[2] Altera Corp.\, “Stratix 10 Device Overview\,” S10-OVERVIEW\, 2 015.12.04\n\n[3] D. M. Hiemstra and V. Kirischian\, "Single Event Upset Ch aracterization of the Kintex-7 Field Programmable Gate Array Using Proton Irradiation\," 2014 IEEE Radiation Effects Data Workshop (REDW)\, Paris\, 2014\, pp. 1-4.\ndoi: 10.1109/REDW.2014.7004593 \n\n[4] M.J. Wirthlin\, H. Takai and A. Harding\, “Soft error rate estimations of the Kintex-7 FPG A within the ATLAS Liquid Argon (LAr) Calorimeter \,” in Proc. of Topica l Workshop on Electronics for Particle Physics 2013\, Perugia\, Italy\n\n[ 5] T. Higuchi\, M. Nakao and E. Nakano\, “Radiation tolerance of readout electronics for Belle II\,” in Proc. of Topical Workshop on Electronics for Particle Physics 2011\, Vienna\, Austria\n\n[6] K. Røed\, J. Alme\, D. Fehlker\, C. Lippmann and A. Rehman\, “First measurement of single ev ent upsets in the readout control FPGA of the ALICE TPC detector\,” in P roc. of Topical Workshop on Electronics for Particle Physics 2011\, Vienna \, Austria\n\n[7] A. Samaras\, A. Varotsou\, N. Chatry\, E. Lorfevre\, F. Bezerra and R. Ecoffet\, "CARMEN1 and CARMEN2 Experiment: Comparison betwe en In-Flight Measured SEE Rates and Predictions\," 2015 15th European Conf erence on Radiation and Its Effects on Components and Systems (RADECS)\, M oscow\, 2015\, pp. 1-6.\ndoi: 10.1109/RADECS.2015.7365590\n\n[8] Xilinx In c.\, “Continuing Experiments of Atmospheric Neutron Effects on Deep Subm icron Integrated Circuits\,” WP286 (v2.0) March 22\, 2016\n\n[9] I. Adac hi\, “Status of Belle II and SuperKEKB\,” Journal of Instrumentation\, Volume 9\, July 2014\n\nhttps://indico.inp.nsk.su/event/8/contributions/1 743/ LOCATION: URL:https://indico.inp.nsk.su/event/8/contributions/1743/ END:VEVENT END:VCALENDAR