Programmable read-only memory device provided with test cells

摘要

A programmable read-only memory device of a junction destruction type is provided with a test circuit for the purpose of detecting a parasitic thyristor effect which may occur in the data programming operation by the user. The test circuit includes first and second additional row lines, a first diode connected between the first additional row line and one column line, a second diode connected between the second additional row line and another column line adjacent to the one column line, and a transistor of a base-open type connected between the second additional row line and the one column line.