Reference voltage generating circuit

A semiconductor integrated circuit has an output end, an N-channel MOS transistor having the drain thereof connected to the output end, and a P-channel MOS transistor having the drain thereof connected to the output end. The semiconductor integrated circuit further has an operational amplifier having the non-inverting input terminal thereof connected to the output end, receiving a voltage at the inverting input terminal thereof, and having the output terminal thereof connected to the gate of the P-channel MOS transistor. In coordination with the P-channel MOS transistor, the operational amplifier operates so as to keep the voltage at the output end equal to the voltage fed thereto.