Semiconductor circuit and power supply circuit

A semiconductor circuit, comprising:

• a first transistor including one end connected to a first node;
• a second transistor including one end connected to a second node, which is different from the first node, and including a gate connected to a gate and the other end of the first transistor;
• a third transistor including one end connected to the other end of the first transistor and including a gate to which a first reference voltage is input;
• a fourth transistor including one end connected to the other end of the second transistor and including the other end connected to the other end of the third transistor;
• a fifth transistor including one end connected to the first node and including a gate connected to the other end of the second transistor;
• and
• an operational amplifier part including a first input end connected to the first node and including a second input end connected to the second node, and configured to input, to a gate of the fourth transistor, a voltage corresponding to a voltage difference between a voltage at the first input end and a voltage at the second input end.