# Light and Power Settings Specification

The Light and Power Settings control the display to save power.

The Light and Power Settings control the lighting of the display under different lighting and power supply conditions. It also controls the idle time required to have elapsed before certain power-saving levels are reached.

Status: RT

## Use Cases

- Quick Suspend

  To help reduce power consumption while on battery power, the user sets the device to dim the light after 10 seconds of inactivity; after another 10 seconds, the light turns off completely (but the screen is still visible by ambient light); after another 10 seconds, the device enters a suspend mode. However, when the device is on mains power, the user sets it to dim the display after 5 minutes, and not power down any further.

- Network download

  While online with a slow connection, the user must often wait for many minutes for downloads and other operations to complete. He therefore configures his device to never suspend while the network is up.

- Automatic light control

  The user configures the screen light to vary automatically based on the amount of ambient light. This way, in dark places the light is low, in medium-lit places it is bright, and in very bright places it is turned off (for reflective displays). (not implemented on current devices)

## Features

- Separate configs for battery and external power: a different configuration of light and power settings is available depending on power source.
- Backlight control: the backlight can be dimmed and turned off after set periods of time.
- Device suspend: the entire device can be powered down to sleep after a set period of time.
- Network influence: an option is provided to not power down if a network is active.
- Screen brightness: the intensity of the screen light can be adjusted.
- Auto: if supported by device hardware, an option is provided to adjust the intensity of the screen light automatically to compensate for ambient lighting conditions (not implemented on current devices).

## Prerequisites

- For automatic light control, light sensor hardware is required.