An integrated circuit for a power supply circuit configured to generate an output voltage of a target level from an alternating current (AC) voltage. The power supply circuit includes a first capacitor and an inductor configured to receive a voltage according to the AC voltage, and a transistor configured to control an inductor current flowing through the inductor. The integrated circuit is configured to switch the transistor, and includes: an identification circuit configured to identify whether a voltage level of an effective value of the AC voltage is a first level or a second level, and a signal output circuit configured to output a driving signal to drive the transistor, and correct the driving signal to thereby correct the input current, in response to the voltage level of the effective value being the first level and the second level, respectively.