DYNAMIC POWER MANGEMENT FOR EMDEDDED SYSTEM

DYNAMIC POWER MANGEMENT FOR EMDEDDED SYSTEM

ABSTRACT

Power management for computer systems has traditionally focused on regulating the power consumption in static modes such as sleep and suspend. These are de-activating states, often requiring a user action to re-activate the system. There are usually significant latencies and overheads for entering and exiting these states, and in desktop and server systems a firmware layer typically supports these modes.
Dynamic power management refers to power management schemes implemented while programs are running, many architectures provide the equivalent of a halt instruction that reduces CPU power during idle periods. The operating system and device drivers may also manage power of peripheral devices. Highly integrated processors with on-board peripherals often include software-controlled clock management capabilities to reduce power consumed by inactive peripherals and peripheral controllers. The memory subsystem also provides a profitable area for dynamic power management, either through the memory controller implementation or through software-based schemes.The dynamic power state of the system must be implemented in the operating system.