User Guide

Nokia Customer Care System Module
Company Confidential RH-21
Issue 2 07/2004  2004 Nokia Corporation. Page 11
User Interface Hardware
LCD
Introduction
RH-21 uses a color GD51 96 x 65 full dot-matrix graphical display. The LCD module
includes LCD glass, LCD COG-driver, spring connector, and metal frame. The LCD module
is included with the lightguide assembly module.
Interface
SW and the control signals are from the UPP asic. The VIO and Vflash1 regulators supply
the LCD with power. The LCD has an internal voltage booster and a booster capacitor is
required between Vout and GND.
Pin 3 (Vss) is the LCD driver's ground. LCD is controlled by UI SW and control signals.
Booster capacitor (C302 1 uF) is connected between booster pin (Vout) and ground. The
capacitor stores boosting voltage.
Keyboard
Introduction
The RH-21 keyboard follows the Jack III style.
PWR key is located on top of phone.
Power Key
All keyboard signals come from UPP asic, except pwr key signal, which is connected
directly to UEM. Pressing of pwr key is detected so that switch of pwr key connects
PWONX is of UEM to GND and creates an interrupt.
Lights
Introduction
RH-21 has LEDs for lighting purposes: two LEDs for keyboard and two LEDs for display.
LED type is TBSF (white).
Interfaces
Both the display and keyboard lights are controlled through a shared LED driver with a
constant current charge-pump circuit. The driver circuit is controlled by the Dlight signal
from UEM. With appropriate SW, the driver can be PWM controlled for dimming purpose.
Technical Information
LED locates in hole and terminals are soldered on the component side of the module
PWB. The LEDs have a white plastic body around the diode, and this directs the emitted
light better to the UI-side.