Proximity Sensor And Ambient Light Sensor (Als); Imaging And Video; Display - Nokia 500 Service Manual

RM-750
System Module

Proximity sensor and ambient light sensor (ALS)

This phone uses a combined proximity and ambient light sensor called DiPro. The proximity part of the device
uses an external IR LED supplied by VBAT. The current this LED consumes is controlled by DiPro and set using
software. The interrupt output of DiPro changes state when the infra red light from the LED is reflected back
by a suitable reflective surface.
Note that when proximity is in use, during a voice call, the proximity sensor detects face and turns off the
display and touch to prevent false key pressing.
The ambient light sensor detects the level of ambient light and adjusts the display and key brightness
accordingly whenever the display is active. Covering this sensor results in dimmed display and key lights.
Figure 27 DiPro proximity sensor and ambient light sensor

Imaging and video

Display

Rapido has an external display buffer with 8Mbit display RAM. The input interfaces for display buffer are
ViSSI-12 for image data and LoSSI for commands.
The data interface between display buffer and display is CDP (Compact Display Port), display commands are
sent by LoSSI interface. The display backlight control is controlled by the display.
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