Optimizing Power Management for Portable Multimedia Devices:Designers of wireless handheld systems have always faced difficult challenges. They must build small, lightweight systems that are both easy to use and durable. At the same time, the success of the systems they design is directly impacted by how long they can run without recharge. Power conservation and optimization is a constant design theme.
Perhaps the greatest challenge these designers face today, however, is optimizing power management in a market that demands constantly evolving feature sets. When most developers design a portable device they center their design around a particular processor and chip set. A power management unit (PMU) is selected to provide power to the system. Typically, that PMU covers most of the power functions including charging the battery, powering the processor and chipsets.
But portable device designs rarely stay the same for long. Invariably first generation products do not provide all the functionality the market demands. More often than not, product developers must add new features to distinguish their product from the competition or customize some existing feature to attract new markets and support new applications. When they do that, the off-the-shelf PMU that accompanies the core chipset will not satisfy the power requirements for that added functionality. Instead, designers must add new power management technologies to build the most power efficient, cost-effective, and compact system the market demands.