To realize the design of a circuit which prevents the occurrence of abnormal operation at a low voltage resulted from power start-up or the like and operates stably at a lower voltage.

A band gap reference circuit has a PNP-type transistor Q1, a Darlington circuit 11 in which Q2 is connected in a Darlington configuration, a Darlington circuit 12 in which PNP-type transistors Q3, Q4 are connected in a Darlington configuration, an operational amplifier 13 which functions as a current control means, P channel type MOS transistors M1 to M4 which function as current sources, resistors R1 to R3, and current-limiting resistors R11, R12, with these generating a reference voltage. The current-limiting resistors R11, R12, at the power start-up or the like, if an output voltage PB of the operational amplifier 13 reaches VSS=0 [V], restrict currents I2, I3 passing through the MOS transistors M2, M3 in order to prevent VN3 from dropping to a level less than VN1, thus stabilizing the operation.