Samsung STH-A225 Service Manual

SERVICE

TDMA MOBILE TELEPHONE

STH-A225

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

DEF

ABC

GHI

MNO

JKL

XYZ

TUV

©Samsung Electronics Co.,Ltd. December. 2001

Pinted in Korea. Code No.: GH68-01930A BASIC.

ELECTRONICS

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1-1

1. STH-A225 Trouble Shooting

1. Baseband Section

1-1. Program No Running

Need to check

Q204, U311

Replace dome S/W

Need to check

Q204, U311

Need to replace

Memory(U206)

Need to check neighbor part

Need to check OSC302,

U202 & neighbor part

Press END Key

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

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1-2

STH-A225 Trouble Shooting

1-2. Abnormal LCD display ,EL Baob Light, Vibrator & Speaker Operation

LCD module

Good

Replace LCD module

Speaker Output OK?

Need to check

CN101 & neighbor part

Need to check

CN101

START

LCD Control

Signal OK?

EL_EN=H

EL Back light

OK?

VCC, ADD(2), DATA(0:7),

DISPLAY_CS, RST

LCD Display Running

Send Command EL

enable(Test mode:176)

Need to check

CN101

VIBRATOR=H

Replace LCD module

Vibrator Run

OK?

LCD Display Running EL Back lingt Running

Send Command Vibrator

enable(Test mode:180)

Need to check CN101

& neighbor part

SPK+,SPKSignal 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’

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1-3

STH-A225 Trouble Shooting

1-3. Abnormal Key, Mic, LED’S operation

Need to check CN102-1

& neighbor part

Need to check CN102-1,

Q102 & neighbor part

Press Keys

Key Dispaly

OK?

Key Display Good

Send Command Main Audio Path ON

(Test mode:031, 131, 136, 187)

Talking Voice at MIC+

Need to check

CN102-1 & neighbor part

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

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1-4

STH-A225 Trouble Shooting

1-4. Abnormal Buzzer Operation

START

Need to check

U104 & AU101

Ringer Signal

OK?

Send Command Ringer Path ON

(Test mode:183)

Replace AU101

Buzzer Sound Output

OK?

Buzzer Operation

Good

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1-5

STH-A225 Trouble Shooting

1-5. Abnormal external Ear_Mic Jack operation

START

Need to check Q103,

U102 & neighbor parts

HS_SENSE=H

Hock Up Ear_Mic Phone in the Jack(U313)

Send Command MIC_BIAS_EN enable Send

Command AMP_EN enable

Audio set Path=HS

(Test mode:187, 185, 032)

Need to check Q103,

U102 & neighbor parts

SEND_END=H

Press Button on the Ear-Jack

Ear_Mic phone

Operation Good

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1-6

STH-A225 Trouble Shooting

2. RF Section

2-1. Call processing and Online Test

DONE

START

Normal SVC?

Check RX path

Set up Call OK?

Check TX path

Measure SINAD/BER

Good?

Check RX path

Measure

Tx Power Good?

Check TX path

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1-7

STH-A225 Trouble Shooting

2-2. Receiver Section (Offline test)

Need to check

U209, U208, U207

Need to check

F306

U301_8=-54dBm

Need to check

F304 & neighbor parts

RF_BAND=L, RX_BAT=H

PLL_ON=H, PON_LC=H

VCTCXO_PC=H, IF_ON=H

PON_VRF3=H

set up 8920B basestation for RX test

Set Base station RX Lev=-50 dBm

Send Command RX path ON

Send Command channel selecton

(Test mode:031)

START

V_LNA_CELL=H

U208_1=H U207_1=H

Need to check

U301 & neighbor parts

F304 input=-34dBm

U304_45=-35dBm

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1-8

STH-A225 Trouble Shooting

AMPSTDMA

Replace U304

Replace

F302

Need to check OSC301,

neighbor parts & U304_1,2,3

Need to check

U207 & neighbor parts

RF loal check

U304_48 Lev=-5dBm

Freq=adjusted freq?

U304_41 Lev=-19dBm

Freq=130.05MHz

U304_34 Lev=-26dBm

Freq=130.05MHz

Need to check

U304, L303, C308, L301, C307

U304_37 Lev=4dBm

Freq=450kHz

Replace F301 or

Need to check R302, R304, C301

U304_25 Lev=-2dBm

Freq=450kHz

MODE

U304_40, 42=3.0V

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1-9

STH-A225 Trouble Shooting

Replace U304

Case TDMA mode:

setup basestation for RX test

Amplitude:-50dBm

U304_9, 19, 11, 12

measure I/Q

Quarature wave

Need to check U304 &

Quad LC Tank circuit

(L310, C328, C330,

C329, R320)

PON_LD=H

Case AMPS mode:

setup basestation for RX test

Audio Freq gen : 1004Hz

FM deviation : 2.9kHz

Y Y

U304_16 DEMOD (sinusoidal wave)

Vp-p=350mV Freq=1004Hz

Need to check U304 &

R327, R323, C353, C107

U101_52 DEMOD (sinusoidal wave)

MAX Vp-p=1.4V

Freq=1004Hz

Replace U203

U101_40 BBCLK=

6.2208MHz or 4.96NHz or

5.12MHz

Replace U203

U101_32RX_CLK=

BBCLK/2 or

BBCLK/8

Replace U203

U101_31 RX_SYNC=

BBCLK/32 or

BBCLK/128

Replace U203

U101_31 RX_DATA=

serial data

DONE

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1-10

STH-A225 Trouble Shooting

2-3.Transmitter Section (Offline test)

Replace U203

U101_40 BBCLK=

6.2208MHz or 4.096MHz or5.12MHz

U101_34 TX_CLK=

BBCLK/32 or BBCLK/8

U101_33 TX_SYNC=

BBCLK/512 or BBCLK/128

U101_33 TX_DATA=

serial data

RF_BAND=L, TX_BAT=H

PLL_ON=H, VCYCXO_PC=H

IF_ON=H, PON_TX=H

PON_VRF3=H

setup 8920B as basestaion for

TX test audio signal?

Send command TX path ON

Send Command channel selection

(Test mode:136, 131)

START

AMPSTDMA

2 1

MODE

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1-11

STH-A225 Trouble Shooting

Replace U101

Need to check

V_RF2=3.0V or

Replace U304

U304_59(RF OUT)

Fc=Local_freq + 175.05

U101_61, 60, 58, 57

TX I/Q Quarature signal

AC Lev Vp_p=0.4V

DC bias Lev=1.5V

U101_63 MOD

(sinusoidal wave)

MAX Vp-p=1.4V

Freq=1004Hz

OSC303_1

(FM modulation out)

Freq=175.05MHz

Audio Freq=1004Hz

Need to check

OSC303,

V_IF_VCO=3.0V

Need to check

U304_66 or

Replace U304

U304_59(RF OUT)

measure Level

Send command PA_CNT

(Test mode:132)

Level is adjustable?

Replace F310

U304_59(RF OUT)

Fc=Local_freq + 175.05

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1-12

STH-A225 Trouble Shooting

Need to check

V_DRV_CELL=3.0V,

neighbor part or

Replace U307

U307 Gain

around 27dB

Replace F309

F309 Insertion loss

around 3dB

Need to check

V_PA_BAIS_CELL(U305_5,6,7)=3.0V

VBATT(U305_14,15,16)=3.2~1V

or Replace U305

U305 Gain

around 30dB

Need to check

F313 & neighbor parts

F306_1 around same power

with U305 output

Need to check

F313 & neighbor parts

F306 insertion loss

under 3dB

DONE

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2-1

2. STH-A225 MAIN Electrical Parts List

0 STH-A225G/TCE 1 GH07-00092A LCD-STHA225 MOTOR, SPK UG-18B75-FGHTX-A, STH-A225, -, 34.6 x 1 GH43-00360A BATTERY-STHA205 LP473465B, STH-A205, LI-ION , 900 mAh, -, 4.2 V, 1 GH44-00145G CHARGER-SCHN105 TC TCH020ABN, SCH-N105, AC/DC, -, -, -, -, 1 GH59-00174A UNIT-KEY PAD ASS’Y STH-A205, HUW9518-010010, -, KEY PAD ASS’Y, -, 1 GH92-00829A PBA MAIN-STHA225 STH-A225, -, BRAZ, MAIN PBA, -, -, -, -, 2 3002-001062 AU101 BUZZER-MAGNETIC 88dB, 3.6 V, 90 mA, 2.731KHz, TP 2 2203-005061 C101 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-005061 C102 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-000254 C103 C-CERAMIC, CHIP 10 nF, 10 %, 16 V, X7R, TP, 1005, 2 2203-005061 C104 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-005061 C105 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-005061 C106 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-005061 C107 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-005061 C108 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-005061 C109 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-005061 C110 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-005061 C111 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-005061 C112 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-005061 C114 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-005061 C115 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-000233 C116 C-CERAMIC, CHIP 0.1 nF, 5 %, 50 V, NP0, TP, 1005 2 2203-000628 C117 C-CERAMIC, CHIP 0.022 nF, 5 %, 50 V, NP0, TP, 1005 2 2203-005061 C118 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-001153 C119 C-CERAMIC, CHIP 0.068 nF, 5 %, 50 V, NP0, TP, 1005 2 2203-001153 C120 C-CERAMIC, CHIP 0.068 nF, 5 %, 50 V, NP0, TP, 1005 2 2203-001153 C121 C-CERAMIC, CHIP 0.068 nF, 5 %, 50 V, NP0, TP, 1005 2 2203-001153 C122 C-CERAMIC, CHIP 0.068 nF, 5 %, 50 V, NP0, TP, 1005 2 2203-001153 C123 C-CERAMIC, CHIP 0.068 nF, 5 %, 50 V, NP0, TP, 1005 2 2203-001153 C124 C-CERAMIC, CHIP 0.068 nF, 5 %, 50 V, NP0, TP, 1005 2 2203-001153 C125 C-CERAMIC, CHIP 0.068 nF, 5 %, 50 V, NP0, TP, 1005 2 2203-001153 C126 C-CERAMIC, CHIP 0.068 nF, 5 %, 50 V, NP0, TP, 1005 2 2203-005061 C127 C-CERAMIC, CHIP 100 nF, +80-20 %, 16 V, Y5 V, TP, 1005 2 2203-000278 C128 C-CERAMIC, CHIP 0.01 nF, 0.5 pF, 50 V, NP0, TP, 1005

Level SEC CODE Design LOC DESCRIPTIONS

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