Anyone experienced a bit error in a configuration PROM? Our design contains a XC18V02 that configures a XCV300 in master serial mode. The design has worked flawlessly for many years, but in recent time three individuals have suddenly stopped configuring on power up. The first two where considered "accidents" and the PROM were simply reprogrammed, after which the units (so far) worked flawlessly. When it happened a third time (three strikes and OUT), it became an issue. Read-back through JTAG revealed a single bit error in the PROM.
All EEPROMS are from the same batch, marked:
XILINX XC18V02 VQ44AEN0117 F1178746A C
Has this happened to anyone else?