A power optimized display memory organization for handheld user terminals

Today´s handheld devices become more and more multimedia capable. One subsystem of a multimedia terminal that accounts for a considerable amount of the total power consumption is the display unit. The backlight is the major culprit there. As new display units without backlights emerge, the data transfers required to put data on the screen start using up an increasingly important part of the platform´s power. We have examined a novel system view that allows for power savings by decreasing the required number of memory accesses to put a frame on the screen. A two-step optimization method for existing platforms is presented. Measurements on a multimedia application show that, on average, power savings of 72% can be obtained on the display related memory accesses. For the proposed optimizations methods to work, it is important that both hardware and software designers become aware of the impact their design-time decisions have on the final power consumption of a system.