Samsung SGH-P730C Service Manual

GSM TELEPHONE

SGH-P738/SGH-P730C

GSM TELEPHONE

CONTENTS

1. Specification

2. Flow Chart of Troubleshooting

3. Exploded Views and Parts List

4. Electrical Parts List

5. PCB Diagrams

6. Block Diagrams

1. SGH-P738 Specification

1. GSM General Specification

GSM900 Phase 1

Freq. Band [MHz]

Uplink/Downlink

ARFCN range 1~124 0~124 & 975~1023 512~885

Tx/Rx spacing 45MHz 45MHz 95MHz

Mod. Bit rate /

Bit Period

Time Slot Period /

Frame Period

Modulation 0.3GMSK 0.3GMSK 0.3GMSK

MS Power 33dBm~13dBm 33dBm~5dBm 30dBm~0dBm

890~915 935~960

270.833kbps

3.692us

576.9us

4.615ms

EGSM 900

Phase 2

880~915 925~960

270.833kbps

3.692us

576.9us

4.615ms

DCS 1800

Phase 1

1710~1785 1805~1880

270.833kbps

3.692us

576.9us

4.615ms

Power Class 5pcl ~ 15pcl 5pcl ~ 19pcl 0pcl ~ 15pcl

Sensitivity -102dBm -102dBm -100dBm

TDMA Mux 8 8 8

Cell Radius 35Km 35Km 2Km

SGH-P738 Speclflcation

2. GSM Tx Power Class

Tx Power

control level

5 33±3dBm 6 31±3dBm 7 29±3dBm 8 27±3dBm

9 25±3dBm 10 23±3dBm 11 21±3dBm 12 19±3dBm 13 17±3dBm 14 15±3dBm 15 13±3dBm 16 11±3dBm 17 9±3dBm 18 7±3dBm 19 5±3dBm

GSM900

Tx Power

DCS1800

control level

0 30±3 dBm

1 28±3 dBm

2 26±3 dBm

3 24±3 dBm

4 22±3 dBm

5 20±3 dBm

6 18±3 dBm

7 16±3 dBm

8 14±3 dBm

9 12±4 dBm

10 10±4 dBm

11 8±4 dBm

12 6±4 dBm

13 4±4 dBm

14 2±5 dBm

15 0±5 dBm

2. SGH-P738 Flow Chart of Troubleshooting and Circuit Diagrams

1. Power On

'Power ON' does not work

check the current

consumption more

than 100mA

Yes

Check the Voltage

of the Battery more

than 3.5V

Yes

Check the pin11 of U101 is more than

2.8V

Yes

Check U101

pin 39 =

2.8V

No No

U101 pin9

Download again

Charge the battery

Check

"Power On"

key?

Yes

=1.8V

check U101 and C117

Check U101 and C116

check keypad

Yes

Check the Initial Operation

Yes

END

Yes

SGH-P738 Flow Chart of Troubleshooting and Circuit Diagrams

2. Initial

Initial Failure

Check the signal at

the pin 21 of U101 is

"High" when the phone

is boot on

Yes

Check pin4 of OSC402

Voltage is 2.8V ?

Yes

Check pin3 of OSC600,

Frequency is 13MHz?

Yes

Check U401

Check pull_up R603,pin39 of U101,

OSC600, C613

Check or change OSC600

Check pin5 of U103

Voltage is 2.5V?

Yes

Check OSC300 is

working?

Yes

END

Check the soldered status of U103,

U401

Check or Change U300

3. Sim Part

*TestwithSim

Phone can't access SIM card

SGH-P738 Flow Chart of Troubleshooting and Circuit Diagrams

Yes

Check the pin 1 of

CN104. voltage 3V?

Yes

Check the SIM

connector's (CN104)

connection to SIM

card

Yes

Check the circuit

around CN104 input

circuitry

Yes

Check the circuit

around U401 output

and voltage supply

circuitty

Check the circuit related to U101

Resolder or change CN104

Check the related circuit of CN104

Check the related circuit of U401 and

U101

END

Yes

SGH-P738 Flow Chart of Troubleshooting and Circuit Diagrams

4.Microphone Part

* Call with Sim before testing.

MicroPhone does not work

Yes

Check the soldered

status of microphone

Yes

Resolder microphone

Check the reference voltage on mic path

C201≒2.0V

Yes

Is microphone OK?

Yes

END

Resolder or change

R203, C209, R204, R201, R200,

C200

Check U501

5.Directional MIC Part

When you play MPEG file, if Audio is not active

Directional MIC does not work

SGH-P738 Flow Chart of Troubleshooting and Circuit Diagrams

Yes

Check MIC "+" terminal,

Bias Voltage = 2.6V?

Yes

Check pin21 of U200,

Voltage = 1.76V?

Yes

Change directional MIC

Resolder R249

Resolder C244

SGH-P738 Flow Chart of Troubleshooting and Circuit Diagrams

6. Speaker Part

*Callbeforetesting.

Receiver does not work

Check the soldered

status of Speaker

Yes

Check the pin 7 of U202

"High"?

Yes

Is Speaker working?

Yes

Is Speaker working ?

Resolder Speaker

Check U202 and the audio path of

U501

Check the path from U501 to CN304

Change Speaker

END

Yes

7. Key Data Input

Check the Initial Operation

SGH-P738 Flow Chart of Troubleshooting and Circuit Diagrams

Check the Keypad &

Dome Sheet

Yes

Check soldered status of

CN302 and connecting

status between KEY-FPCB

and PBA

Yes

When "#"pad pressed,

Pin 11 of

CN302=2.8V(high)?

Yes

Replace or Adjust

the Keypad & Dome Sheet

ResolderCN302orchangeFPCB

Check U401

END

SGH-P738 Flow Chart of Troubleshooting and Circuit Diagrams

8. LCD backlight

Backlight does not work

Backlight "ON" mode in

the menu?

Yes

Check conecting

between PBA and LCD

conector

Yes

Check CN304 pin 28=

"high"?

Yes

END

Select backlight "ON" mode

Check FPCB

Check the LCD

+ 23 hidden pages