There is provided a technique that includes: a first transistor used as an input, which is installed on a path through which a current to be regulated flows; a second transistor used as an output, which is connected to the first transistor to form a current mirror circuit; a resistor installed on a path of a current flowing through the second transistor; a stabilizing circuit configured to match an operating point of the second transistor with an operating point of the first transistor; and a transistor controller configured to regulate a voltage to be supplied to a control terminal of the first transistor according to a current detection signal that corresponds to a voltage drop across the resistor.