| 摘要 |
<p>PURPOSE:To effectively perform write and to realize readout in arbitrary bit unit, by adapting an input circuit for the write to a universal PROM writer. CONSTITUTION:The selection operation of the data line of a memory array M-ARY is performed by a Y selection circuit YSEL1 in the universal PROM writer in a write mode. And the circuit YSEL1 selects the data line of the array M-ARY corresponding to a designated Y address signal AY1, and performs a selection operation to connect the data line to an input/output circuit IOB. In such a case, the input/output circuit IOB for the confirmation of the write and the designation of readout is provided, and the column selection signal of the circuit is set at a high voltage in a write operation and at a low voltage in a readout operation. Next, as for the data line in the array M-ARY, a different data line from that in the write operation is selected in a readout mode by a Y selection circuit YSEL2, and is outputted via a readout circuit RA.</p> |
