A display driver includes internal oscillator circuitry, timing controller circuitry, and panel interface circuitry. The internal oscillator circuitry is disposed internal to the display driver and configured to generate an internal oscillation signal. The timing controller circuitry is configured to generate a resultant sync signal using an external sync input received from an entity external to the display driver during a first period of a frame period. The timing controller circuitry is further configured to generate the resultant sync signal using the internal oscillation signal during a second period of the frame period, the second period following the first period. The panel interface circuitry is configured to generate, based on the resultant sync signal, an emission control signal that controls emission scan driver circuitry configured to drive a plurality of emission scan lines of a display panel.