Antifuse circuitry for post-package dram repair

摘要

The anti-fuse circuit includes three sub-blocks: a multiplexer having inputs of control signals and addresses and yielding the activation of a programming signal and program addresses; a programming voltage generator consisting of an oscillator and a charge pump; and an anti-fuse unit circuits for the program/read of anti-fuse states. For an anti-fuse program at the special test mode, a program address generation circuit having inputs of control signals and addresses activates the programming voltage generator and makes a special or program address for selection of anti-fuse. In the normal mode, the program address generation circuit and an internal power generator remain at an inactive state. In anti-fuse unit circuit, the program address and the programming voltage signal from the programming voltage generator serve to switch the terminal of the anti-fuse up to a programming voltage level when the anti-fuse is selected for programming of anti-fuse elements.