A half-power buffer amplifier includes a buffer stage having a first-half buffer stage and a second-half buffer stage. An output of the first-half buffer stage is controllably fed back to a rail-to-rail differential amplifier, and an output of the second-half buffer stage is controllably fed back to the rail-to-rail differential amplifier. A switch network controls the connection between the outputs of the buffer stage and an output node of the half-power buffer amplifier in a manner such that a same pixel, with respect to different frames, of a display panel is driven by the same rail-to-rail differential amplifier.