Time-Resolved Studies of Single-Event-Upset effects in Optical Data Receiver for the First LHC Upgrade Phase of the ATLAS Pixel Detector.

Abstract

1 Speaker PoS(RD11)038 Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence.http://pos.sissa.it An optical receiver board housing an amplifier-and-decoding ASIC designed in 130 nm CMOS process for use with bi-phase-mark encoded input signals, coupled to a PiN-photodiode array, was exposed to a proton beam of 24 GeV/c momentum at CERN. At the same time a reference receiver board containing the same ASIC but coupled to an electrical input-signal-source was also exposed to the proton beam. The 40 MHz clock and 40 Mbps data signals encoded together and supplied to the devices under test, were restored directly on both boards and then transmitted back to the counting room for on-line checking of consistency. In the case of a data-bit error or a missing clock transition, indicating an occurrence of a SEU, a sequence of time aligned data-bits and corresponding clock-states were recorded and in part as oscilloscope-waveforms for off-line analyses. Measurements were performed using a custom-developed FPGA-based DAQ system, for input signals covering a certain range of optical and electrical amplitudes. We present results obtained from the 2010 run at the CERN irradiation facility, including the SEU rate and cross-section dependence on input signal amplitude, for various types of effects on clock and data consistency, along with the time-resolved structure of the SEU incidents.