This memo looks specifically at the effects of cosmic ray radiation at the high ALMA site on the ALMA Correlator. The most vulnerable components of the Correlator are the 17,066 Xilinx Field Programmable Gate Arrays (FPGA). The primary risk is that radiation would cause bits in the downloaded configuration to change. This could change the FPGAs functionality, until reloaded. The most practical remedy is to periodically download the Xilinx personalities. This would reverse the effects of a rare error induced by radiation.
View a pdf version of ALMA Memo #462.
Download a postscript version of ALMA Memo #462.
View related documentation entitled "The NSEU Response of Static Latch Based FPGAs".
Last modified: 2003-12-02
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