Nokia E72, Руководство по обслуживанию

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The keyboard illumination is handled by a separate LED driver. The driver is controlled by I2C bus.
Optical navi key interface
The optical finger navigation (OFN) sensor is connected to I2C bus. Two GENIOs are reserved for interrupts
and two others for reset and shutdown functions.
The OFN sensor captures the image of finger print and detects the direction of finger movement. This is done
by using IR LED whose light is reflected from the finger to the sensor through a lens.
Ambient light sensor (ALS) interface
Ambient light sensor information is used to control keyboard and display brightness.
•
Keyboard backlight is turned OFF, when it is not needed.
•
Display brightness is dimmed, when environment lighting is dark.
The ambient light sensor is calibrated in production and can be re-tuned in service points, though not
recommended unless calibration coefficient is lost for some reason.
For ALS interface, see the System module block diagram in
Phone description (page 6–5) .
Accelerometer
The accelerometer measures the static acceleration of gravity in tilt-sensing applications, as well as dynamic
acceleration resulting from motion or shock.
It has the following features:
•
2.16V to 3.6V supply voltage
•
1.8V compatible IOs
•
Low power consumption
•
±2g/±8g dynamically selectable scale
•
I
2
C/SPI digital output interface
• Embedded self test
•
10000g high shock survivability
• Pb free/RoHS compliancy
The accelerometer (N1102) is connected to I2C. One GENIO is reserved for interrupt.
For accelerometer interface, see the System module block diagram in
Phone description (page 6–5) .
Magnetometer
The device has an I2C controlled 3-axis magnetometer for compassing purpose.
The magnetometer has the following features:
• 3-axis magnetometer device suitable for compass application
•
Built-in A to D converter for magnetometer data out
• Self test function
•
I2C bus interface
• Power modes: OFF mode, stand-by mode and active mode
•
DRDY function for measurement data ready
• INT function to inform exceeding magnetic field strength threshold.
The operating temperature is -20°C to +85°C.
The operating supply voltages are:
RM-529; RM-530; RM-584
System Module
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