A power circuit for a liquid crystal display includes a voltage divider which generates a voltage-divided voltage between a first power source and a second power source, an operational amplifier which receives the voltage-divided voltage to output a driving voltage, a first switch connected between the first power source and a common node, and a second switch connected between the second power source and the common node. The first switch provides a first current path between the first power source and the common node in response to the driving voltage, and the second switch provides a second current path between the second power source and the common node in response to the driving voltage.