Nokia RM-57, Руководство по обслуживанию

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2 Normal Partial mode, 260k colors but only part of the display is active
The module includes:
• FPWB foil including connector and discretes and driver circuits
• display panel (glass)
• drivers including display controller and 176 x 208 x 18 bits RAM
• backlight system: lightguide, LEDs and necessary optical sheets
• supporting mechanics
• metal frame (stainless steel)
• plastic frame
The interconnection between the LCD module and the Nokia engine is implemented with a 24-pin board-to-
board connector.
Display is controlled via MeSSi-8 interface by Helen3. All MeSSi-8 signals go through the EMC filtering ASIPs.
The display module does not require any tunings in service.
Keyboard
The device keyboard is connected to the main PWB with a board-to-board connector.
The keymatrix has six rows and four columns. The voice key on the main PWB and the navigation key are
connected to the same keymatrix.
Table 18 Keymatrix
Col3 Col2 Col1 Col0
Row0 Right Left Right soft key Left soft key
Row1 Down Up Send Select
Row2 8 3 2 7
Row3 6 1 5
Row4 # * 9
Row5 4 Voice End
Row6 Apps Clear Edit 0
Display and keyboard backlight
The device has one Led Driver (SMPS) that is used to drive both display and keyboard LEDs.
Both display LEDs (4pcs) and keyboard LEDs (4pcs) are connected in series.
Current adjustment of the driver is done from the display LED branch, and keyboard current also depends on
the display brightness.
In a typical use case, keyboard LEDs are turned ON only in dark ambient lighting conditions.
Control signals for LED driver are:
From To Voltage Function
GenOut1 TAHVO R2302 (10k) 0V / 1.8V Maximum current
control (0V ->max
curr.)
GenOut2 TAHVO R2301 (4k7) 0V / 1.8V
RM-57/58
System Module
Nokia Customer Care
Issue 1 Company Confidential Page 9–21
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