Samsung STH-A225 User manual

SERVICE
TDMA MOBILE
TELEPHONE
STH-A225
2
C
ABC
4
GHI
13
DEF
5
JKL
6
MNO
7
PQRS
8
TUV
0
9
WXYZ
Manual
TDMA MOBILE TELEPHONE CONTENTS
1. Trouble Shooting
2. Electrical Parts List
3. Exploded Views and Parts List
4. Block Diagrams
5. PCB Diagrams
6. Circuit Description &
Circuit Diagrams

©Samsung Electronics Co.,Ltd. December. 2001
Pinted in Korea.
Code No.: GH68-01930A
BASIC.
ELECTRONICS

SAMSUNG Proprietary-Contents may change without notice
1-1
1. STH-A225 Trouble Shooting
1. Baseband Section
1-1. Program No Running
N
Need to check
Q204, U311
N
Replace dome S/W
N
Need to check
Q204, U311
N
Need to replace
Memory(U206)
N
Need to check neighbor part
Need to check OSC302,
U202 & neighbor part
Press END Key
Y
Y
Y
Y
Y
Y
ON_SW=H
VBAT>3.2V
VCTCXO_IN=14.4 MHz
32K_XIN=32.768 kHZ
Memory (U206)
control signal OK?
VCC=3.0V
V_VCTCXO=3.0V
RST=3.0V
IVCC=2.2V
BOOT=H
Program Running
VCC, ADD(0:21), DATA(0:15),
FLASH_CS, SRAM_CS, UBE,
MEMOEB, MEMWEB

SAMSUNG Proprietary-Contents may change without notice
1-2
STH-A225 Trouble Shooting
1-2. Abnormal LCD display ,EL Baob Light, Vibrator & Speaker Operation
Y
LCD module
Good
N
Replace LCD module
Y
Speaker Output OK?
N
Need to check
CN101 & neighbor part
N
Need to check
CN101
START
Y
Y
LCD Control
Signal OK?
Y
Y
EL_EN=H
N
Y
EL Back light
OK?
VCC, ADD(2), DATA(0:7),
DISPLAY_CS, RST
LCD Display Running
Send Command EL
enable(Test mode:176)
N
Need to check
CN101
Y
Y
VIBRATOR=H
N
Replace LCD module
Y
Vibrator Run
OK?
LCD Display Running
EL Back lingt Running
Send Command Vibrator
enable(Test mode:180)
N
Need to check CN101
& neighbor part
Y
SPK+,SPK-
Signal OK?
LCD EL Vibrator OK Send Command
Main Audio Receiver Path ON
(Test mode:031, 131, 134, 185)
Need to check U106 out pin5
2.8 V al control pin3 ‘H’

SAMSUNG Proprietary-Contents may change without notice
1-3
STH-A225 Trouble Shooting
1-3. Abnormal Key, Mic, LED’S operation
N
Need to check CN102-1
& neighbor part
N
Need to check CN102-1,
Q102 & neighbor part
Press Keys
Y
Y
Key Dispaly
OK?
Y
Key Display Good
Send Command Main Audio Path ON
(Test mode:031, 131, 136, 187)
Talking Voice at MIC+
N
Need to check
CN102-1 & neighbor part
Y
Y
Y
LED Operation
OK?
Key Display Good
Mic Path Good
Send Command ALT_LED_ON
Send Command SVC_LED_ON
Send Command LED_ON
(Test mode:178)
Audio signal output
at Speaker?
GOOD