A display driver circuit is configured to drive a display panel having a multiplexer. A method for the display driver circuit includes steps of: sending, by the display driver circuit, a plurality of first data voltages to the display panel through a switch of the multiplexer; and outputting, by the display driver circuit, a control signal to the switch during a first period in which the plurality of first data voltages sent through the switch remain unchanged, wherein the control signal controls the switch to be turned on and keep in a conducted status until the display driver circuit sends a second data voltage different from the plurality of unchanged first data voltages through the switch.