A control method for charging time sharing in a display apparatus, which includes receiving image data including a plurality of pixel data signals corresponding to a plurality of display driving periods, each display driving period associated with pixel data signals of a respective row of the display apparatus, calculating a plurality of gray variations corresponding to the plurality of display driving periods according to the plurality of pixel data signals, adjusting the plurality of display driving periods to generate a plurality of adjusted display driving periods according to the plurality of gray variations, and generating a gate clock signal according to the plurality of adjusted display driving periods.