A semiconductor circuit (10a) comprises a first terminal section (17) to be connected to a connection point of two external resistors; a second terminal section (18) to be connected to an external circuit; a voltage circuit section having a first terminal connected to the second terminal section (18); a reference voltage circuit section (102) which outputs a predetermined voltage; an operational amplifier (104) having a first input terminal connected to the reference voltage circuit section (102), a second input terminal connected to the first terminal section (17), and an output terminal connected to a second terminal of the voltage circuit section; an abnormality detecting circuit which detects an abnormal voltage of the first terminal section (17); a normal signal generating unit (130) which generates a normal signal; and a switching circuit which, when the abnormality detecting circuit detects the abnormal voltage, does not output a voltage based on the first terminal section (17) to the second terminal section (18) and instead outputs a normal voltage based on the normal signal to the second terminal section (18).