A method for controlling voltage output is disclosed. The method is used to control a power supply module to provide a required operating voltage to a display panel, and a display frame of the display panel comprises a plurality of sequential row driving periods, each row driving period comprising a charging period and a non-charging period, wherein during the charging period, a connection between a data line and a corresponding row of sub-pixels is enabled so that data voltages are written into the corresponding sub-pixels. The method comprises controlling the power supply module to output an operating voltage at a preset first operating frequency during a display of a picture to be displayed, wherein a time period during which the power supply module outputs the operating voltage to the display panel does not overlap with the charging period of each row driving period.