| 摘要 |
PURPOSE:To allow a right operation speed, by changing the output potential of a potential generation mean in non-reversible manner. CONSTITUTION:A P channel MOS transistor 1 and a fuse element 2 are connected in series between the point of the impression of positive polarity source voltage VDD and the point of the impression of earth voltage VSS, and the gate of the MOS transistor 1 is connected to the point of VSS impression. To series connection point of the MOS transistor 1 and the fuse element 2, the gates of the P channel MOS transistor 3 and the N channel MOS transistor 4 are connected, and the potential VO is outputted from both series connection point. When the fuse element 2 is not fused, in oder that the MOS transistor 3 is ON, and the MOS transistor 4 is OFF, the output potential VO becomes the VDD side potential VH. On the other hand, when the fuse element 2 is fused, the MOS transistor 3 becomes OFF, and the MOS transistor 4 becomes ON, and accordingly the output potential VO becomes the VSS side potential VL. Since the fuse element, 2 once fused, does not return to the original, the change from the potential VH to the potential VL is regarded as a non-reversible change. |
