| 摘要 |
PURPOSE:To provide a redundant circuit which enables one to perform various tests using the redundant circuit after a product assembly is completed by temporarily writing in changeover data to the redundant circuit provided in the semiconductor storage device with a redundancy. CONSTITUTION:A first changeover element TU is consisting of nonvolatile memory cell and a second changeover element TE is consisting of elements, such as EPROM, which can write in or erase data. A test mode setting circuit 1 outputs an operating mode setting signal A which sets an operating mode based on the inputted signal IT from a test terminal 10, a changeover element controlling circuit 2 selects the first or the second element TU or TE based on the signal A. Should at least either one of the changeover elements TU or TE has data written, then, a NOR circuit 15 outputs an output signal O as a changeover completed signal. |
