| 摘要 |
PURPOSE:To use a p-type MOS transistor and to obtain an output circuit for a semiconductor device fit for speed-up by providing a transistor on whose gate the sum of a supply voltage and a threshold voltage is impressed between a pull-up transistor and a pull-down transistor. CONSTITUTION:For example, an n-type transistor 6 is connected between a p-type pull-up transistor 5 and an n-type pull-down transistor 7, and the gate potential of the n-type transistor 6 is boosted to (a supply voltage VCC + a threshold voltage VTHN of the transistor 6). Consequently, even when an output terminal becomes higher than the supply voltage VCC, the source potential of the pull-up transistor 5 is clamped by the supply voltage VCC. Thus, even when the p-type MOS transistor is used as a pull-up transistor 5, the p-type MOS transistor can be held off and therefore, the generation of a leak current can be prevented. Since a high output voltage is also boosted to the level of the supply voltage, working speed can be increased. |
