Abstract:
An electronic device may be provided with a housing such as a metal housing in which a display is mounted. Control circuitry in the electronic device such as a system-on-chip integrated circuit may produce image data. A display driver integrated circuit may receive the image data from the system-on-chip integrated circuit and may display the image data on the display. In the absence of electrostatic discharge, the display driver integrated circuit may operate normally and may generate a heartbeat signal. When disrupted due to electrostatic discharge, the display driver circuitry may cease production of the heartbeat signal. The system-on-chip integrated circuit can implement a watchdog timer. If the watchdog timer times out because the heartbeat signal is not received within a timeout period, the system-on-chip integrated circuit may reset the display.
Abstract:
Systems and methods for efficiently generating display driver timing signals are provided. In one example, display driver circuitry of an electronic display may provide a negative voltage from a negative voltage supply to display control circuitry during a first period and may provide a positive voltage from a positive voltage supply to the display control circuitry during a second period. After providing the negative voltage during the first period but before providing the positive voltage during the second period, the display driver circuitry may precharge the capacitance of the display control circuitry to ground. In this way, the positive voltage supply substantially does not supply charge to raise the voltage on the capacitance of the display control circuitry from the negative voltage to ground.