Delete comment from: Ken Shirriff's blog
For crypto modules, blowing additional fuses can be done to erase the key. So, indeed, a very positive security implication. Corrupting the key is enough to make the module unusable, but the key is recoverable if only a few bits were affected. Once the majority of the key is "blown", i.e. overwritten, the key material is forever secure from recovery.
I've found a cache of new old stock MMI PALs in Norway of all places, and they are delightful devices to use. Excellent for TTL homebrew computer projects - they save on discrete chips. In fact, that case of chips was so big that thousands of them were tossed away already, but still quite a few remain :)
Apr 28, 2025, 11:44:04 AM
Posted to Looking inside a 1970s PROM chip that stores data in microscopic fuses