Als Technical Description And Troubleshooting; Proximity Sensor And Ambient Light Sensor (Als); Proximity Tuning - Nokia RM-626 Service Manual

RM-626
BB Troubleshooting and Manual Tuning Guide

ALS technical description and troubleshooting

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 11 DiPro proximity sensor and ambient light sensor

Proximity tuning

Prerequisites
Note: Tuning should be done only if the sensor/chassis is changed!
Steps
1. Place the phone to the calibration jig.
2. Make sure that the Kodak90% reflector is 50 mm above the proximity sensor.
3. Set the phone to Local mode with Phoenix.
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