| 摘要 |
PURPOSE:To attain the operation at a wide chip power voltage region by providing a circuit branch comprising an NMOS transistor (TR) between the input terminal and the gate side node of a transmission MOS TR. CONSTITUTION:NMOS TRs 12, 13 as the circuit branch are provided between the input terminal 9 and the gate side node N1 of the transmission MOS TR 4. Other circuit is the same as a conventional circuit. When the level of an output terminal 10 is L, the input voltage at the input terminal 9 is not sent to the terminal 10. In case of precharging the terminal 10, the gate voltage of the MOS TR 4 rises by capacitors 5, 6 and when the gate voltage gets higher by the threshold voltage of the MOS TRs 12, 13, the MOS TRs 12, 13 are turned on and the voltage at the gate side node N1 does not exceed the voltage of (input voltage +threshold voltage). Thus, the overvoltage of the gate of the MOS TR 4 is prevented. |
