Function Overview; Description; General; 2.1 Mechanical Design - Sony Ericsson K800 Electrical Repair Manual

DESCRIPTION

1

General

The Sony Ericsson Mobile Communication phone K800 is a 3G dual mode mobile phone
supporting WCDMA and triple band GSM/GPRS in the 900, 1800 and 1900 frequency bands. The
phone is a GPRS class 10 terminal supporting voice, circuit switched (CS) and packet switched
(PS) data. This Sony Ericsson dual mode 3G product is designed to be compatible with all
mandatory GSM phase 2+ recommendations.
The phone has an in-built antenna, a 3.2 Mega Pixel Camera with a lens cover and an associated
xenon fl ash, a VGA-Camera for Video Call, a Display, and a slot for a Memory Stick M2 external
memory.
There is only one size of battery. A connector at the bottom of the phone makes it possible
to connect various accessories like chargers and hands-free units. A USB cable can also be
connected to the bottom connector. The external antenna connector can be used to connect to an
external antenna, disconnecting the internal phone antenna.
The electronic functions are divided into RF parts, logic/audio parts, opto-electronic parts,
Bluetooth parts, an IR transceiver, and an FM radio. The electronics parts consists of the main
PCB with components placed on both sides, the Key-Flexible-PCB that has Key-Matrix-circuit/
LEDs, loudspeaker box with the internal antenna, ear speaker, microphone, vibrator, 3.2 mega
pixel camera, xenon fl ash module, VGA camera, the Display, Bluetooth module, and FM radio
parts. The RF parts are mainly housed in separate modules.
Antenna RF
Flash
VGA Camera
3.2 MPix Camera
Baseband
Transmitter
Control
Receiver
DC and Return
Bluetooth
3,6V battery IR
Figure 1. Block diagram of the K800.
2 Transceiver
This description provides only a simple general description of the transceiver section and its
components.

FUNCTION OVERVIEW

Logic / audio
CPU
TDMA/CDMA
DSP
AF part
Display
Keyboard
FM radio
Description

2.1 Mechanical Design

The phone is built up around a core unit consisting of a plastic frame with the BT antenna
mounted on which the assembled PCB, the cameras, the vibrator, a plastic LCD holder and
the LCD, a plastic keyboard support plate and the keyboard dome foil, the loud speaker box
with loudspeaker and antenna, and the xenon fl ash module are mounted. This core unit is then
snapped and screwed in the front cover together with the keys, joystick, and the M2 cover. The
antenna cover with the sliding camera lens cover is then mounted. The battery fi ts in a dedicated
cavity and is covered with a battery cover.
Dimensions
Length 106mm
Width 47mm
Thickness 18mm (22mm across the lens cover)
Weight 115g

2.2 RF parts

2.2.1 GSM 900
The GSM 900 part of the transceiver is including E-GSM and has a frequency range spanning
from 925.2 to 959.8 MHz for the receiver, and from 880.2 to 914.8 MHz for the transmitter. This
gives 174 channels with 200kHz channel separation. The TX – RX frequency separation is always
45MHz.
2.2.2 GSM 1800
The GSM 1800 part of the transceiver has a frequency range spanning from 1805.2 to 1879.8
MHz for the receiver, and from 1710.2 to 1784.8 MHz for the transmitter. This gives 374 channels
with 200kHz channel separation. The TX – RX frequency separation is always 95MHz.
2.2.3 GSM 1900
The GSM 1900 part of the transceiver has a frequency range spanning from 1930.2 to 1989.8
MHz for the receiver, and from 1850.2 to 1909.8 MHz for the transmitter. This gives 299 channels
with 200kHz channel separation. The TX – RX frequency separation is always 80MHz.
2.2.4 WCDMA
The WCDMA part of the transceiver has a frequency range spanning from 2110 to 2170 MHz for
the receiver, and from 1920 to 1980 MHz for the transmitter. This gives 12 channels with 5MHz
channel separation. The TX – RX frequency separation is always 190MHz.
2.2.5 RF architecture
VCXO
A voltage controlled crystal oscillator (VCXO) running at 13 MHz is used as a reference for all
frequencies generated in the transceiver.
SEMC Electrical Repair Manual
K800 - K810
1202-3085 rev. 2 3 (121)