Nokia 603, Руководство по обслуживанию

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User interface
Touch module
This phone uses Atmel capacitive touch solution.
The Atmel touch module is interfaced to I2C bus of RAPU. RAPU’s GenIO123 is used for Touch INT.
The Atmel touch module operates with VAUX1 supply output from EM ASIC.
Whenever the user touches the touch screen, the controller raises an interrupt to RAPU which initiates I2C
transactions to identify the locations the user touches on the display.
Figure 51 Touch system block diagram
Proximity Sensor and Ambient Light Sensor (ALS)
This phone uses a combined Proximity and Ambient Light Sensor called DiPro (N1104). DiPro (Digital Proximity
Sensor) is connected to RAPU via a single GENIO (INT=GENIO3) and I2C_0 bus. Supply voltage for DiPro ASIC is
VAUX1 (2.8 V). The Infrared LED used with the Proximity Sensor is supplied by VBAT.
The Proximity Sensor is an optical reflective sensor comprising of an IR LED and a photodetector IC. DiPro sets
the IR LED on and at the same time the photodetector measures the reflected radiation.
One of the typical applications of the Proximity Sensor is for using the INT output as an indication to SW of
a phone being present near to human ear while attending a call. In such a case, the human body will act as
a reflector, due to which more IR rays fall on the photodetector. If irradiance is higher than the limit set by
SW, the INT goes from LOW to HIGH. This LOW to HIGH transition is used as an indication to SW of the presence
of a reflector (human body in this case). SW can then switch off the display and deactivate the touch panel.
Similarly, when the user moves the phone away from the ear, INT goes from HIGH to LOW. This is an indication
to SW that there is no reflector nearby and that the display and touch panel should be switched on and the
touch panel activated.
The Ambient Light Sensor detects the level of ambient light and adjusts the display and key brightness to
enable improved display contrast and energy saving. Covering the Ambient Light Sensor results in dimmed
display and key lights.
RM-779
System Module
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