A driving device of a display apparatus includes: a gate driver, a gate on voltage modulator, and a signal controller. The gate driver includes a plurality of gate driving circuits, each of the gate driving circuits being configured to: generate a gate signal according to a gate control signal, and apply the gate signal to at least one gate line. The gate on voltage modulator is configured to: modulate a gate on voltage according to a modulation control signal, and generate a first modulated gate on voltage. The signal controller is configured to generate the modulation control signal and the gate control signal. At least one of the plurality of gate driving circuits includes an amplifier configured to: receive the first modulated gate on voltage, and output a second modulated gate on voltage including substantially the same waveform as the first modulated gate on voltage.