Colin Walls, Mentor Graphics
embedded.com (August 21, 2015)
Power consumption by embedded devices is a critical issue. There is always a need to extend battery life and/or reduce the environmental impact of a system. Historically, this was purely a hardware issue, but those days are past. In modern embedded systems software takes an increasing responsibility for power management. This article reviews how power management is achieved while a device is operating and looks at the techniques employed to minimize power consumption when a device is inactive.
There are broadly two contexts in which a device's power consumption may be considered: when it is in use and when it is idle. In the former, active power management is the key requirement; in the latter, the deployment of low power CPU modes may be advantageous.