| 摘要 |
PROBLEM TO BE SOLVED: To fabricate a semiconductor integrated circuit configured to operate on a plurality of systems of power supplies by a standard CMOS process.SOLUTION: There is a voltage switching circuit including: a decoder for selecting either a voltage VD3 or a voltage VSS to be output as a first signal in response to a signal ERS, selecting either a voltage VD5 (>VD3) or the voltage VSS to be output as a second signal in response to a signal VFY, and outputting a third signal in the same voltage range in response to the first and second signals; a level shifter LS3 for converting a first logic signal into a fourth signal in the range of a voltage VDDH (≥VD5) to the voltage VD5 to output it; a buffer BUF1 for buffering and outputting the second and third signals; and selection means HVSW1 for outputting any one of the voltage VDDH, the voltage VD3 and a voltage VSWL as a voltage VWL in response to the fourth signal and the buffered second and third signals. |
