| 摘要 |
PURPOSE: To operate a memory device as a volatile memory in design stage and to operate it as a non-volatile memory when design is completed. CONSTITUTION: A first anti-fuse A1 is provided for a memory cell 10 and the first anti-fuse A1 is operated so that the memory cell 10 can be set to a non- volatile state. A pair of inverters I1 and I2 which are cross-connected are provided for the memory cell 10. The first anti-fuse A1 is connected between the output of one inverter in the cross-connected inverters and the ground. The first anti-fuse A1 is operated and the memory cell is set to the first non-volatile state. Then, a second anti-fuse A2 is connected between an output B and a power voltage Vcc , and it is operated so as to set the memory cell in the second non-volatile state. Then, only the anti-fuse A or A2 is programmed in the memory cell. |
