Programmable read-only memory device

Claim 1

A bipolar PROM device having a plurality of memory cells which are located at respective cross positions of a plurality of word lines and a plurality of bit lines and which are selected by word address signals and bit address signals applied to said PROM device, said PROM device comprising: a word address buffer for amplifying said word address signals; a word address decoder for decoding the word address signals from said word address buffer; one or more bit address buffers for amplifying said bit address signals; a first bit address decoder for decoding the bit address signals from said bit address buffer for writing-in of information; a second bit address decoder for decoding the bit address signals from said one or more bit address buffers for reading-out of information, at least one of said first and second bit address decoders being composed of a plurality of AND gates, each of said AND gates comprising an output terminal and a plurality of PNP type transistors each comprising an emitter, a base, and a collector, to each said base of said transistors being applied the address signals from said bit address buffer, each said collector of said transistors being connected commonly to ground, and each said emitter of said transistor being connected commonly to said output terminal of said AND gate; a program circuit for initially writing-in information to the selected memory cells; and a multiplexer for reading-out information from the selected memory cells.