That already happened on Xilinx Zynq FPGAs, where an incorrect power supply sequence causes random writes to one of the internal buses, which overwrites various

That already happened on Xilinx Zynq FPGAs, where an incorrect power supply sequence causes random writes to one of the internal buses, which overwrites various eFuses, even after they have been locked. https://support.xilinx.com/s/question/0D52E00006hpKdKSAU/zynq-arm-core-1-bricked-due-to-efuse-bit-corruption?language=en_US https://support.xilinx.com/s/question/0D52E00006hpKdKSAU/zyn... I understand burning eFuses is necessary during production, but having them blowable when the device is operating normally could be compared to building disposable devices. One logic or software error and the device can be bricked permanently. That is a ridiculous state of affairs. What about single event upsets or some EMI induced glitch causing eFuse corruption? The power for burning the important fuses should be off at all times during normal operation. And we can have a test pad to supply the VPP during production. In the case of the AMD processors, a separate bank of fuses can be used to store diagnostic data for warranty returns, if necessary. If those get corrupted somehow, the device won't malfunction. But the important ones should not be possible to program after manufacturing, no matter what happens to the logical state of the hardware, period.