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If the rationale of using diodes in ROM (rather than simple wires) is to prevent the matrix being shorted together, then why does shorting not occur for programmable ROM - which has blowable fuse connections?

Apologies if should not be starting a new thread for this; please note that the question is inspired by an answer here What is the rationale of using diode matrix in ROM , but I don't have sufficient 'rep' to comment my question there.

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    \$\begingroup\$ Asking a new question and cross-referencing to the old one is the correct procedure on this site. +1. \$\endgroup\$ – Transistor Feb 19 at 7:13
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Fuse-programmable ROM is not a simple wired XY matrix, with fuses at each intersection. That wouldn't work, for the reasons you give.

Typically, transistors are used at each intersection, like this.

enter image description here

Image from here, worth visiting if you're interested in other types of ROM.

Conceptually, something as simple as a diode in series with each fuse would serve to both allow reading, and selection of the appropriate fuse to blow. However, there's a lot of development and technology between the basic idea, and a commercial product. Interestingly, many fuse ROMS use 'anti-fuses'. In the right process, high voltage can punch through the dielectric layer of a capacitor and make it fail short more reliably and cheaply than high current can open a fuse.

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