Electronic devices with displays are configured to provide a gamma correction signal to each source driver chip driving the display. The gamma correction signal is supplied by a gamma application circuit coupled to each source driver chip. The gamma application circuit includes a switching amplifier configured to output a switching waveform and a filter to input the switching waveform and output the gamma correction signal to an input of each source driver chip. The switching amplifier functions as a switching power supply having improved power efficiency compared to conventional gamma application circuits.