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CDMA TELEPHONE
SPH-A900




CDMA TELEPHONE CONTENTS

1. General Introduction
2. Circuit Description
3. Installation
4. NAM Programming
5. Product Support Tools
6. Test Procedure

7. Flow Chart of Troubleshooting
8. Exploded Views and Parts List
9. Block Diagram
10. Electrical Parts List
11. PCB Diagrams
Samsung Electronics Co.,Ltd ember. 005
2
Printed in Korea.
This Service Manual is a property of Samsung Electronics Co.,Ltd.
Any unauthorized use of Manual can be punished under applicable Code No.: GH68-08836A
International and/or domestic law.
BASIC.
1. General Introduction

1-1. General Instruction

The SPH-A900 enables mobile users to communicate 3G CDMA2000 1X service into a single handset.


For CDMA/PCS mode, The SPH-A900 supports Release A of the CDMA2000 1X standard.


The SPH-A900 also features EV-DO high-speed data, Bluetooth as well as a swiveling 1.3 megapixel
digital camera.
This stylish clamshell phone supports dual color displays, Bluetooth, MMS, voice dialing, airplane mode
and EV-DO services.




1-1
SAMSUNG Proprietary-Contents may change without notice
This Document can not be used without Samsung's authorization
General Introduction




1-2

SAMSUNG Proprietary-Contents may change without notice
This Document can not be used without Samsung's authorization
2. Circuit Description

2-1. Logic Section
2-1-1. Power Supply
Press "END" key to turn on the phone and then the V_BAT and ON_SW signals will be connected. This
turns on the inner regulators(V_MSMCORE, V_MSMC, VPD, VPA) of u200(MAX1526).
The V_BAT applied to ON_SW will change ON_SW_SENSE signal from HIGH to LOW.
MSM6500(UCP102) sends out PS_HOLD(logical HIGH) to keep the inner regulators on even after the
"END" key is released. V_RFRX can be turned on/off by the RX_CTRL signal. V_TCXO can be turned
on/off by the TCXO_CTRL signal. The other regulators(VDD2.6, V_SYNTH, V_RFTX, MOTOR_EN) will be
in the ON/OFF state by I2C-compatible 2 wire serial interface.
The regulated Voltage(u200, V_MSMCORE) are used in the core of MSM.

The regulated Voltage(u200, V_MSMC) are used in the digital part of MSM.
The regulated Voltage(u200, VPD) are used in the digital part and memory of MSM.
The regulated Voltage(u200, VPA) is used in the analog part of MSM.
The regulated Voltage(u200, V_RFTX) is used in the Tx RF part.
The regulated Voltage(u200, V_RFRX) is used in the Rx RF part.
The regulated Voltage(u200, V_TCXO) is used in the TCXO.

The regulated Voltage(u200, V_SYNTH) is used in the PLL part.
The regulated Voltage(u200, VDD2.6) is used in the voltage of camera .
The regulated Voltage(u200, MOTOR_EN) is used in the MOTOR.



2-1-2. Inner Charging Circuit Part
The most important function of the charger shall be done in the PMIC(Power Management Circuit u200).
When the phone with a battery is connected with a travel charging adapter, the inner charging circuit of
the PMIC(u200) will charge the battery by constant fast charge mode.
When battery reaches regulation voltage of 4.2V (default charging voltage for Li+mode), the charge
current drops quickly to 0mA
- Input voltage range : 4.25