Hi John,Having C code to look at would be good, but something generated automatically by this Actum software might be very hard to read.
It occurred to me that maybe the EEPROM is getting hit by electrical effects. Apparently there is an on-chip charge pump which produces a voltage higher than Vdd, and perhaps that's vulnerable to a hostile environment where the rest of the chip is safer. But I'd still look very hard for anything that might be writing to the EEPROM when you don't expect it.
I wonder if there's any way that Microchip could figure out the nature of the damage to the EEPROM, if you sent them the damaged chips. But probably that's a kind of service that they won't do unless you pay them.
Thanks! I have asked Actum Solution to make a C-code out of my project. I have made many of this curciut, and use a standard 5V regulator, and also why after one year, if there should be some noisy / sparks or something, it should happend more random. Normalle I use PIC16F689, and nearly same code, and never seen problems. Let see what happend. Actum Solution have the whole project, and they are VERY godd specialist. I will of cource be back. Regards Per