Process of Programming Kills FPGA
We have had some instances where programming an FPGA appears to kill the FPGA.
For instance, we had two boards that has a Cyclone III and wouldn't program because Quartus said it couldn't access the JTAG chain. We measured low resistance on the programming header. Then we removed the FPGAs and found that the low resistance was gone. Then we replaced the FPGAs and the low resistance was still gone. However, the first one I tried to program came up with the same error and the programming header had low resistance again (6 ohms on the TMS signal). The second one programmed properly.
We are using the power supplies on the board to power and they look clean.
We are using an Altera USB blaster to program.
Unfortunately I didn't measure for low resistance right after powering the board and before programming but I will after we replace the Cyclone III again.
What in the process of powering and programming the board could kill some FPGAs but not others?