A display apparatus includes a power supply device. The power supply device includes a power supply part and an integrated circuit chip. The power supply part outputs a first power to drive a backlight and a second power to drive a main circuit. The integrated circuit chip increases, based on a control signal to adjust a brightness of the backlight being received, a current value of the second power, and reduces, based on the control signal not being received for a first threshold time, the current value of the second power.