| 摘要 |
PURPOSE:To perform the low voltage operation of a microcomputer incorporating a read-only memory(EPROM) by enabling an operation to be performed even under a low voltage by attaching a control circuit. CONSTITUTION:The EPROMs 2a-2d in the microcomputer incorporating the EPROM are comprised of a readout circuit 1 which reads out data in the EPROM and transfers it to the microcomputer, the EPROM 2 whose threshold voltage is lowered to enable the low voltage operation to be performed, and an inverter 3 to be attached to perform the normal readout of a ROM even when the threshold voltage is lowered. Thereby, the readout of the EPROM 2 can be performed under the low voltage by lowering the threshold voltage of the EPROM 2, and furthermore, the low voltage operation of the microcomputer incorporating the EPROM can be performed by prohibiting the readout of an unselected EPROM 2 by attaching the inverter 3. |
