An integrated circuit includes: a power supply circuit configured to generate a supply voltage from at least one of first and second power source voltages; and a system load configured to operate by receiving the supply voltage through an output node of the power supply circuit, wherein the power supply circuit includes: a first low drop-output (LDO) regulator configured to generate, from the first power source voltage, a first load current flowing to the system load through the output node; and a second LDO regulator configured to selectively generate a second load current flowing to the system load through the output node, from the second power source voltage based on a difference between voltages of internal nodes of the first LDO regulator.