LG MS20 Service Manual

Date: December, 2007 / Issue 1.0

Service Manual

MS20

Service Manual

Model : MS20

Internal Use Only

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1. INTRODUCTION.................................. 5

1.1 Purpose ...................................................... 5

1.2 Regulatory Information ............................... 5

2. PERFORMANCE ..................................7

2.1 System Overview.........................................7

2.2 Usable environment.....................................8

2.3 Radio Performance......................................8

2.4 Current Consumption.................................12

2.5 RSSI BAR ..................................................12

2.6 Battery BAR ...............................................13

2.7 Sound Pressure Level ...............................14

2.8 Charging ....................................................14

3. TECHNICAL BRIEF............................15

3.1 General Description ...................................15

3.2 GSM Mode.................................................17

3.3 LO generation and distribution circuits ......21

3.4 Off-chip RF Components ...........................21

3.5 Digital Baseband(DBB/MSM7200) ............29

3.6 Hardware Architecture ...............................30

3.7 Subsystem(MSM7200) ..............................32

3.8 Power Block...............................................34

3.9 External memory interface.........................39

3.10 H/W Sub System .....................................41

3.11 Main Features..........................................67

4. TROUBLE SHOOTING.......................73

4.1 RF Component ..........................................73

4.2 SIGNAL PATH_GSM RF ...........................76

4.3 Checking VCTCXO Block ..........................77

4.4 Checking Front-End Module Block ............79

4.5 Checking GSM Block.................................81

4.6 Checking Bluetooth Block..........................87

4.7 Power ON Troubleshooting .......................89

4.8 Charger Troubleshooting ...........................92

4.9 USB Troubleshooting.................................95

4.10 SIM Detect Troubleshooting ....................97

4.11 Camera Troubleshooting .........................99

4.12 Keypad Backlight Troubleshooting ........101

4.13 Main LCD Troubleshooting ....................102

4.14 Receiver Path ........................................103

4.15 Headset path .........................................105

4.16 Speaker phone path ..............................107

4.17 Main microphone ...................................109

4.18 Headset microphone..............................111

4.19 Vibrator ..................................................113

5. DOWNLOAD .....................................115

5.1 Introduction ..............................................115

5.2 Downloading Procedure ..........................115

5.3 Troubleshooting Download Errors ...........125

5.4 Caution ....................................................127

6. BLOCK DIAGRAM ...........................128

6.1 GSM RF Block .........................................128

6.2 Interface Diagram ....................................130

7. Circuit Diagram................................133

8. BGA IC PIN MAP..............................143

9. PCB LAYOUT ...................................149

10. Calibration & RF Auto Test

Program (Hot Kimchi) ...................157

10.1 Configuration of HOT KIMCHI ...............157

10.2 How to use HOT KIMCHI.......................160

11. Phone Test Mode _ 3G smart

Phone MS25 ...................................162

12. EXPLODED VIEW & REPLACEMENT

PART LIST ..................................... 169

12.1 EXPLODED VIEW ................................ 169

12.2 Replacement Parts

<Mechanic component> ....................... 171

<Main component> ............................... 173

12.3 Accessory ............................................. 187

Table Of Contents

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1.1 Purpose

This manual provides the information necessary to repair, calibration, description and download the features of this model.

1.2 Regulatory Information

A. Security

Toll fraud, the unauthorized use of telecommunications system by an unauthorized part (for example, persons other than your company’s employees, agents, subcontractors, or person working on your company’s behalf) can result in substantial additional charges for your telecommunications services. System users are responsible for the security of own system. There are may be risks of toll fraud associated with your telecommunications system. System users are responsible for programming and configuring the equipment to prevent unauthorized use. The manufacturer does not warrant that this product is immune from the above case but will prevent unauthorized use of commoncarrier telecommunication service of facilities accessed through or connected to it. The manufacturer will not be responsible for any charges that result from such unauthorized use.

B. Incidence of Harm

If a telephone company determines that the equipment provided to customer is faulty and possibly causing harm or interruption in service to the telephone network, it should disconnect telephone service until repair can be done. A telephone company may temporarily disconnect service as long as repair is not done.

C. Changes in Service

A local telephone company may make changes in its communications facilities or procedure. If these changes could reasonably be expected to affect the use of the phones or compatibility with the net work, the telephone company is required to give advanced written notice to the user, allowing the user to take appropriate steps to maintain telephone service.

D. Maintenance Limitations

Maintenance limitations on the phones must be performed only by the manufacturer or its authorized agent. The user may not make any changes and/or repairs expect as specifically noted in this manual. Therefore, note that unauthorized alternations or repair may affect the regulatory status of the system and may void any remaining warranty.

1. INTRODUCTION

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E. Notice of Radiated Emissions

This model complies with rules regarding radiation and radio frequency emission as defined by local regulatory agencies. In accordance with these agencies, you may be required to provide information such as the following to the end user.

F. Pictures

The pictures in this manual are for illustrative purposes only; your actual hardware may look slightly different.

G. Interference and Attenuation

A phone may interfere with sensitive laboratory equipment, medical equipment, etc. Interference from unsuppressed engines or electric motors may cause problems.

H. Electrostatic Sensitive Devices

ATTENTION

Boards, which contain Electrostatic Sensitive Device (ESD), are indicated by the sign. Following information is ESD handling:

• Service personnel should ground themselves by using a wrist strap when exchange system boards.

• When repairs are made to a system board, they should spread the floor with anti-static mat which is also grounded.

• Use a suitable, grounded soldering iron.

• Keep sensitive parts in these protective packages until these are used.

• When returning system boards or parts like EEPROM to the factory, use the protective package as described.

1. INTRODUCTION

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2. PERFORMANCE

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2.1 System Overview

2. PERFORMANCE

Item Specification

Shape GSM850/1800/1900 - Bar type Handset

Size 99.8 X 58 X 12.9 mm

Weight Under 92.5g (with 1050mAh Battery)

Power 3.7 V normal, 1050 mAh Li-Polymer

Talk Time

Over 150 min (GSM, Tx=Level 5, Voice)

(with 1050mAh)

Standby Time

Over 400 Hrs (GSM, Paging period=9)

(with 1050mAh)

Antenna Internal type

LCD Main 2.8” 262K 240 X 320 pixel (TFT)

LCD Backlight White LED Back Light

Camera Auto Focus - 2.0 Mega pixel (CMOS)

Vibrator Yes (Coin Type)

LED Indicator Yes

MIC Yes

Receiver Yes

Earphone Jack Yes (18 pin)

Connectivity Bluetooth, USB

Volume Key Push Type(+, -)

External Memory Yes

I/O Connect 18 Pin

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2.2 Usable environment

1) Environment

2) Environment (Accessory)

* CLA : 12 ~ 24 V(DC)

2.3 Radio Performance

1) Transmitter - GSM Mode

* In case of DCS : [A] -> 1710, [B] -> 1785 * In case of PCS : [A] -> 1850, [B] -> 1910

2. PERFORMANCE

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Item Specification

Voltage 3.7 V(Typ), 3.2 V(Min), [Shut Down : 3.2 V]

Operation Temp -20 ~ +60°C

Storage Temp -20 ~ +70°C

Humidity 85 % (Max)

Reference Spec. Min Typ. Max Unit

TA Power Available power 100 220 240 Vac

No Item GSM DCS & PCS

100k~1GHz -39dBm

9k ~ 1GHz -39dBm

MS allocated 1G~[A]MHz -33dBm

Channel

1G~12.75GHz -33dBm

[A]M~[B]MHz -39dBm

Conducted [B]M~12.75GHz -33dBm

1 Spurious 100k~869MHz -60dBm 100k~869MHz -60dBm

Emission 869M~894MHz -62dBm 869M~894MHz -62dBm

Idle Mode

894M~1GHz -60dBm 894M~1GHz -60dBm

1G~[A]MHz -50dBm 1G~[A]MHz -50dBm

[A]M~[B]MHz -56dBm [A]M~[B]MHz -56dBm

[B]M~12.5GHz -50dBm [B]M~12.5GHz -50dBm

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2. PERFORMANCE

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* In case of DCS : [A] -> 1710, [B] -> 1785 * In case of PCS : [A] -> 1850, [B] -> 1910

No Item GSM DCS & PCS

30M ~ 1GHz -36dBm

30M~1GHz -36dBm

MS allocated 1G~[A]MHz -30dBm

Channel

1G ~ 4GHz -30dBm

[A]M~[B]MHz -36dBm

Radiated [B]M~4GHz -30dBm

2Spurious 30M ~ 869MHz -57dBm 30M~869MHz -57dBm

Emission 869M~894MHz -59dBm 869M~894MHz -59dBm

Idle Mode

894M~1GHz -57dBm 894M~1GHz -57dBm

1G~[A]MHz -47dBm 1G~[A]MHz -47dBm

[A]M~[B]MHz -53dBm [A]M~[B]MHz -53dBm

[B]M~4GHz -47dBm [B]M~4GHz -47dBm

3 Frequency Error ±0.1ppm ±0.1ppm

4 Phase Error

±5(RMS) ±5(RMS)

±20(PEAK) ±20(PEAK)

3dB below reference sensitivity 3dB below reference sensitivity

Frequency Error RA250 : ±200Hz RA250: ±250Hz

5 Under Multipath and HT100 : ±100Hz HT100: ±250Hz

Interference Condition TU50 : ±100Hz TU50: ±150Hz

TU3 : ±150Hz TU1.5: ±200Hz

0 ~ 100kHz +0.5dB 0 ~ 100kHz +0.5dB

200kHz -30dB 200kHz -30dB

250kHz -33dB 250kHz -33dB

Due to 400kHz -60dB 400kHz -60dB

Output RF

modulation 600 ~ 1800kHz -66dB 600 ~ 1800kHz -60dB

6 1800 ~ 3000kHz -69dB 1800 ~ 6000kHz -65dB

Spectrum

3000 ~ 6000kHz -71dB ≥6000kHz -73dB

≥6000kHz -77dB

Due to

400kHz -19dB 400kHz -22dB

Switching

600kHz -21dB 600kHz -24dB

transient

1200kHz -21dB 1200kHz -24dB

1800kHz -24dB 1800kHz -27dB

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2. PERFORMANCE

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No Item GSM DCS & PCS

Frequency offset 800kHz

7 Intermodulation attenuation –

Intermodulation product should

be Less than 55dB below the

level of Wanted signal

Power control

Power Tolerance

Power control

Power Tolerance

Level (dBm) (dB) Level (dBm) (dB)

533±3 030±3

631±3 128±3

729±3 226±3

827±3 324±3

925±3 422±3

10 23 ±3 5 20 ±3

8 Transmitter Output Power 11 21 ±3 6 18 ±3

12 19 ±3 7 16 ±3

13 17 ±3 8 14 ±3

14 15 ±3 9 12 ±4

15 13 ±3 10 10 ±4

16 11 ±5 11 8 ±4

17 9 ±5 12 6 ±4

18 7 ±5 13 4 ±4

19 5 ±5 14 2 ±5

15 0 ±5

9 Burst timing Mask IN Mask IN

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2. PERFORMANCE

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2)Receiver - GSM Mode

No Item GSM DCS & PCS

1

Sensitivity (TCH/FS Class II) -105dBm -105dBm

2

Co-Channel Rejection

C/Ic=7dB Storage -30 ~ +85

(TCH/FS Class II, RBER, TU high/FH)

3 Adjacent Channel 200kHz C/Ia1=-12dB C/Ia1=-12dB

Rejection 400kHz C/Ia2=-44dB C/Ia2=-44dB

Wanted Signal :-98dBm 1st Wanted Signal :-96dBm 1st

4

Intermodulation Rejection interferer:-44dBm 2nd interferer:-44dBm 2nd

interferer:-45dBm interferer:-44dBm

5

Blocking Response Wanted Signal :-101dBm Wanted Signal :-101dBm

(TCH/FS Class II, RBER)

Unwanted : Depend on Frequency Unwanted : Depend on Frequency

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2. PERFORMANCE

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2.4 Current Consumption

1) MS25 Current Consumption

(Stand by and Voice Call Test Condition : Bluetooth off, LCD backlight off,Neighbor Cell off)

2) MS25 Current Consumption

(Stand by and Voice Call Test Condition : Bluetooth off, LCD backlight off,Neighbor Cell off)

2.5 RSSI BAR

Stand by Voice Call VT

GSM

Under 3.00 mA Under 350 mA

Paging=9 period (PCL=5)

Level Change GSM

BAR 4 → 3 -91 ± 2 dBm

BAR 3 → 2 -96 ± 2 dBm

BAR 2 → 1 -101 ± 2 dBm

BAR 1 → 0 -106 ± 2 dBm

Stand by Voice Call VT

GSM

Under 2.7 mA Under 270 mA

Paging=5 period (PCL=7)

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2.6 Battery BAR

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Indication Standby

Bar 4 100% ~ 76%

Bar 4 → 3 75%

Bar 3 → 2 50%

Bar 2 → 1 25%

Bar 1 → Empty 5%

Low Voltage Battery Alarm 10%

Very Low Battery Alarm 5%

Power Off 3.20 ± 0.05V / 0%

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2. PERFORMANCE

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2.7 Sound Pressure Level

2.8 Charging

• Charging Method : CC & CV (Constant Current and Constant Voltage)

• Maximum Charging Voltage : 4.2 V

• Maximum Charging Current : 900 mA

• Normal Battery Capacity : 1050 mAh

• Charging Time : Max 2.5 hours (except for trickle charging time)

• Full charging indication current (charging icon stop current) : 60 mA

• Cut-off voltage : 3.20 V

No Test Item Specification

1 Sending Loudness Rating (SLR) 8 ±3 dB

2 Receiving Loudness Rating (RLR)

Nor 2 ± 3 dB

Max -13 dB

3 Side Tone Masking Rating (STMR) Min 23 dB

4 Echo Loss (EL) Min 46 dB

5 Idle Noise-Sending (INS) Max -64 dBm0p

6 Idle Noise-Receiving (INR)

Nor

Under -54 dBPA

Max

7 Sending Loudness Rating (SLR) 8±3dB

8 Receiving Loudness Rating (RLR)

Nor -1 ±3 dB

Max -12 ±3 dB

9 Side Tone Masking Rating (STMR) Min 25 dB

10 Echo Loss (EL) Min 40 dB

11 Idle Noise-Sending (INS) Max -55 dBm0p

12 Idle Noise-Receiving (INR)

Nor Under -45 dBPA

Max Under -40 dBPA

TDMA Noise

-. GSM : Power Level : 5

DCS/PCS : Power Level : 0

(Cell Power : -90 ~ -105 dBm)

13

-. Acoustic (Max Vol.)

MS/Headset SLR : 8 ±3dB

MS/Headset RLR : -15 ± 3dB/-12

dB

(SLR/RLR : Mid-value setting)

MS

Headset

MS and

Headset

Max

Under -62 dBm

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3. TECHNICAL BRIEF

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3.1 General Description

The MS25 supports GSM-850, DCS-1800, and PCS-1900 based GSM/GPRS/EDGE. All receivers use the radioOne1Zero-IF architecture to eliminate intermediate frequencies, directly converting signals between RF and baseband. The quad-band GSM transmitters use a baseband-to-IF upconversion followed by an offset phase-locked loop that translates the GMSK-modulated or 8-PSK-modulated signal to RF.

1

QUALCOMM’s branded chipset that implements a Zero-IF radio architecture.

3. TECHNICAL BRIEF

MODE Select

Interface

Vocoder

MP3 / MIDI

GPIO

ARM1136J

GSM/GPRS/EDGE

SBI

Integrated

CODEC

ARM926EJS

MMC

gpsOne

RF Interface

UMTS/HSDPA

TX DACs

RX ADCs

USB OTG

UART 2 / USIM

UART 1

JTAG Interface

PLL

MSM7200

4

2

3

2

UART 3

2

Camera

Graphics

Video

HK ADCs

Memory I/F

EBI1

EBI2

RF Mobile SW

IMT

GSM LB

IMT

LB

HB

AGC

LPF

LO Generation

& Distribution

LO Generation

& Distribution

PLL

SBI

LPF

LO Generation

& Distribution

LO Generation

& Distribution

LPF

PLL

RTR6275

GSM HB

Switchplexer

PA

GSM

GSM SAW

4

MCP Memory

NAND Flash: 256MB

DDR SDRAM : 64MB

MCP Memory

NAND Flash: 256MB

DDR SDRAM : 64MB

DDR SDRAM

PM7540

USB Data

48.00 MHz(for USB)

32.768 kHz (Sleep X-tal)

2

6 JTAG for Test

MIC

HPH

2

TX,RX

VC-TCXO

19.2MHz

RCV +/-

NAND

USB Data

19.2MH z

DM Port

USIM

I/O Port

BT

2

[Fig 1.1] Block diagram of RF part

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A generic, high-level functional block diagram of MS25 is shown in Figure 1-1. One antenna collects base station forward link signals and radiates handset reverse link signals. The antenna connects with receive and transmit paths through a FEM(Front End Module).

In the receiver path, the received RF signals are applied through their band-pass filters and downconverted directly to baseband in the RTR6275 transceiver IC. These baseband outputs are routed to the MSM IC for further signal processing.

The GSM/EDGE transmit path employs one stage of up-conversion and, in order to improve efficiency, is divided into phase and amplitude components to produce an open-loop Polar topology:

1. The on-chip quadrature up-converter translates the GMSK-modulated signal or 8-PSK modulated signal, to a constant envelope phase signal at RF;

2. The amplitude-modulated (AM) component is applied to the ramping control pin of Polar power amplifier from a DAC within the MSM

MS25 power supply voltages are managed and regulated by the PM7540 Power Management IC. This versatile device integrates all wireless handset power management, general housekeeping, and user interface support functions into a single mixed signal IC. It monitors and controls the external power source and coordinates battery recharging while maintaining the handset supply voltages using low dropout, programmable regulators.

The device’s general housekeeping functions include an ADC and analog multiplexer circuit for monitoring on-chip voltage sources, charging status, and current flow, as well as userdefined off-chip variables such as temperature, RF output power, and battery ID. Various oscillator, clock, and counter circuits support IC and higher-level handset functions. Key parameters such as under-voltage lockout and crystal oscillator signal presence are monitored to protect against detrimental conditions.

3. TECHNICAL BRIEF

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3. TECHNICAL BRIEF

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3.2 GSM Mode

3.2.1 GSM Receiver

The Dual-mode MS25’s receiver functions are split between the three RFICs as follows:

• GSM-850, DCS-1800, and PCS-1900 modes bot use the RTR6275 IC only. Each mode has independent front-end circuits and down-converters, but they share common baseband circuits (with only one mode active at a time). All receiver control functions are beginning with SBI2-controlled parameters.

RF Front end consists of antenna, antenna switch module(LMSP43QA-539-TEMP) which includes 3 RX saw filters(GSM850, DCS and PCS). The antenna switch module allows multiple operating bands and modes to share the same antenna. In MS25, a common antenna connects to one of five paths: 1) GSM-850 Rx, 2) GSM-850 Tx, 3) DCS-1800 Rx, 4) DCS-1800, PCS-1900 Tx(High Band Tx’s share the same path), and 5) PCS-1900 Rx. GSM850, DCS, and PCS operation is time division duplexed, so only the receiver or transmitter is active at any time and a frequency duplexer is not required.

2

The RFIC operating modes and circuit parameters are MSM-controlled through the proprietary 3-line Serial Bus Interface (SBI). The Application Programming Interface (API) is used to implement SBI commands. The API is documented in AMSS Software - please see applicable AMSS Software documentation for details.

[Table 1.1] Antenna Switch Module Control logic

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The GSM850, DCS, and PCS receiver inputs of RTR6275 are connected directly to the transceiver front-end circuits(filters and antenna switch module). GSM850, DCS, and PCS receiver inputs use differential configurations to improve common-mode rejection and second-order non-linearity performance. The balance between the complementary signals is critical and must be maintained from the RF filter outputs all the way into the IC pins

Since GSM850, DCS, and PCS signals are time-division duplex (the handset can only receive or transmit at one time), switches are used to separate Rx and Tx signals in place of frequency duplexers this is accomplished in the switch module.

The GSM850, DCS, and PCS receive signals are routed to the RTR6275 through band selection filters and matching networks that transform single-ended 50-Ω sources to differential impedances optimized for gain and noise figure. The RTR input uses a differential configuration to improve second-order intermodulation and common mode rejection performance. The RTR6275 input stages include MSMcontrolled gain adjustments that maximize receiver dynamic range.

The amplifier outputs drive the RF ports of the quadrature RF-to-baseband downconverters. The downconverted baseband outputs are multiplexed and routed to lowpass filters (one I and one Q) having passband and stopband characteristics suitable for GMSK or 8-PSK processing. These filter circuits include DC offset corrections. The filter outputs are buffered and passed on to the MSM7200 IC for further processing

3. TECHNICAL BRIEF

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[Fig 1.2] RTR6275 RX feature

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3.2.2 GSM Transmitter

The RTR6275 transmitter outputs(DA_HB2_OUT and DA_LB1_OUT)include on-chip output matching inductors. 50ohm output impedance is achieved by adding a series capacitor at the output pins. The capacitor value may be optimized for specific applictions and PCB characteristics based on pass-band symmetry about the band center frequency, the suggested starting value is shown in Figure1.3.

The RTR6275 IC is able to support GSM 850 and GSM 1800/1900 mode transmitting. This design guideline shows a tri-band GSM application.

Both high-band and low band outputs are followed by resistive pads to ensure that the load Presented to the outputs remains close to 50ohm. The low-band GSM. Tx path also includes a Tx-band SAW filter to remove noise-spurious components and noise that would be amplified by the PA and appear in the GSM Rx band

3. TECHNICAL BRIEF

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[Fig 1.3] GSM Transmitter matching

6pF

4pF

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300Ω300Ω

8Ω

300Ω300Ω

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3. TECHNICAL BRIEF

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3.3 LO generation and distribution circuits

The integrated LO generation and distribution circuits are driven by internal VCOs to support various modes to yield highly flexible quadrature LO outputs that drive all GSM/EDGE band upconverters and downconverters; with the help of these LO generation and distribution circuits, true zero-IF architecture is employed in all GSM band receivers and transmitters to translate the signal directly from RF to baseband and from baseband to RF.

Two fully functional fractional-N synthesizers, including VCOs and loop filters, are integrated within the RTR6275 IC. The first synthesizer (PLL1) creates the transceiver LOs that support all four GSM band receivers and transmitters including: GSM 850, GSM 900, GSM 1800, and GSM 1900. An external TCXO input signal is required to provide the synthesizer frequency reference to which the PLL is phase and frequency locked. The RTR6275 IC integrates most of PLL loop filter components on-chip except two off-chip loopfilter series capacitors, and significantly reduces off-chip component requirement. With the integrated fractional-N PLL synthesizers, the RTR6275 has the advantages of more flexibleloop bandwidth control, fast lock time, and low-integrated phase error

3.4 Off-chip RF Components

3.4.1 VCTCXO (X500 : TG-5010LH (19.2M))

The Voltage Controlled Temperature Compensated Crystal Oscillator (VCTCXO) provides the reference frequency for all RFIC synthesizers as well as clock generation functions within the MSM7200 IC. The oscillator frequency is controlled by the MSM7200 IC.s TRK_LO_ADJ pulse density modulated signal in the same manner as the transmit gain control TX_AGC_ADJ. A two-pole RC lowpass filter is recommended on this control line.

The PM7540 IC controls the handset power-up sequence, including a special VCTCXO warm-up interval before other circuits are turned on. This warm-up interval (as well as other TCXO controller functions) is enabled by the MSM TCXO_EN line . The PM7540 IC VREG_TCXO regulated output voltage is used to power the VCTCXO and is enabled before most other regulated outputs.

Any GSM mode power control circuits within the MSM7200 IC require a reference voltage for proper operation and sufficient accuracy. Connecting the PM7540 IC REF_OUT directly to the MSM6275 IC GSM_PA_PWR_CTL_REF provides this reference. This sensitive analog signal needs a 0.1 µF low frequency filter near to MSM side, and isolate from digital logic and clock traces with ground on both sides, plus ground above and below if routed on internal layers.

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3.4.2 Front-End Module (FL502 : LMSP43QA-539-TEMP)

This equipment uses a single antenna to support all handset operating modes, with an antenna switch module select the operating frequency and band. The active connection is MSMselected by two control lines (GPIO[75] and GPIO[74]). These GPIOs are programmed to be ANT_SEL0 and ANT_SEL1 respectively.

3. TECHNICAL BRIEF

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[Table 1.2] Front End Module control logic

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3.4.3 PMIC Functional Block Diagram (U304 : PM7540)

• Complete power management, housekeeping, and user interface\e functions for wireless devices (CDMA, non-CDMA handsets, and PDAs)

• Input power management

- Valid external supply attachment and removal detection

- Supports unregulated (closed-loop) external charger supplies and USB supplies as input power sources

- Supports lithium-ion main batteries

- Trickle, constant current, constant voltage, and pulsed charging of the main battery

- Supports coin cell backup battery (including charging)

- Battery voltage detectors with programmable thresholds

- VDD collapse protection

- Charger current regulation and real-time monitoring for over-current protection Charger transistor protection by power limit control

- Control drivers for two external pass transistors and one external battery MOSFET (MOSFET is optional)

- Voltage, current, and power control loops

- Automated recovery from sudden momentary power loss

• Output voltage regulation

- One boost (step-up) switched-mode power supply (SMPS) for driving white LEDs and hosting USB-OTG

- Four buck (step-down), switched-mode power supplies for efficiently generating MSMC1, MSMC2, MSME, and PA supply voltages

- Supports dynamic voltage scaling (DVS) for MSMC1, MSMC2, and PA outputs

- 18 low-dropout regulator circuits with programmable output voltages, implemented using three different current ratings: 300 mA (four), 150 mA (ten), and 50 mA (four). These can be used to power MSMA, MSMP, MSME2, MMC, RFRX1, RFRX2, RFTX, TCXO, SYNT, RUIM1, RUIM2, USB, WLAN, MDDI, CAM, BT, AUX1, and AUX2 circuits.

- One MIC bias regulator circuit

- All regulators can be individually enabled/disabled for power savings

- Low power mode available on most regulators

- All regulated outputs are derived from a common bandgap reference (close tracking)

• Integrated handset -level housekeeping functions reduces external parts count, size, and cost

- Analog multiplexer selects from five internal and up to 28 external inputs

- Multiplexer output’s offset and gain are adjusted, increasing the effective ADC resolution

- Adjusted multiplexer output is buffered and routed to an MSM device ADC

- Dual oscillators: a 32.768 kHz off-chip crystal and an on-chip RC assure MSM device sleep clock

- Crystal oscillator detector and automated switch-over upon lost oscillation

- Real-time clock for tracking time and generating associated alarms

- On-chip adjustments minimize crystal oscillator frequency errors

- Control TCXO warm-up and synchronize, deglitch, and buffer the TCXO signal

- TCXO buffer control for optimal QPH/catnap timing

- Multistage over temperature protection (smart thermal control)

3. TECHNICAL BRIEF

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• Integrated handset -level user interfaces

- Four programmable current sinks recommended as keypad backlight, LCD backlight, camera flash, and general-purpose drivers

- Vibration motor driver programmable from 1.2 to 3.1 V in 100 mV increments

- Two-channel speaker driver with programmable gain, turn-on time, and muting; configurable inputs and outputs capable of stereo or mono operation (drives external 8- speakers with volume controlled 500 mW, eac h channel)

- Video (TV) amplifier allows use as a camcorder or for slide presentations

• IC -level interfaces

- Configurable SBI (three-wire or single-wire) for efficient initialization, status, and control

- Supports MSM interrupt processing with an internal interrupt manager

- Many functions monitored and reported through real-time and interrupt status signals

- Dedicated circuits for controlled poweron sequencing, including the MSM device’s reset signal

- Several events continuously monitored for triggering poweron/poweroff sequences

- Supports and orchestrates soft resets

- USB-OTG transceiver for full-speed (12 Mb/s) and low-speed (1.5 Mb/s) interfacing of the MSM device to computers as a USB peripheral, or connecting the MSM device to other peripherals

- Two sets of RUIM level translators enable MSM device interfacing with external modules

• 22 multipurpose pins that can be configured as digital or analog I/Os, bidirectional I/Os, or current sinks; default functions support the two sets of RUIM level translators, poweron circuits, analog multiplexer inputs, an LED driver, and a selectable reference voltage output

• Highly integrated functionality in a small package - 137-pin CSP with a several center ground pins for electrical ground, mechanical stability, and thermal relief

3. TECHNICAL BRIEF

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[Figure 1.4] MSM7200 Interface

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[Figure1.5] PM7540 Block Diagram

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3. TECHNICAL BRIEF

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3.4.4. GSM PAM (U501:TQM7M5008)

The TQM7M5008 is an extremely small (7 x 7 mm), GSM/EDGE PAM for handset applications. This module has been optimized for excellent EDGE efficiency and Pout in a Polar Loop environment at EDGE class E2+ operation while maintaining high GSM/GPRS efficiency.

The small size and high performance is achieved with high-reliability 3rdgeneration InGaP HBT technology. With 50Ω and output, no external matching or bias components are required.

The module incorporates two highly-integrated InGaP power amplifier die with a CMOS controller. Each amplifier has three gain stages with on-die inter-stage matching implemented with a high Q passives technology for optimal performance. The CMOS controller implements a fully integrated power control within the module for GSM operations, and serves as the AM/AM path in EDGE operations. This eliminates the need for any external couplers, power detectors, current sensing etc., to assure the output power level. The module has Tx enable and band select inputs. Module construction is a low-profile overmolded landgrid array on laminate.

[Figure 1. 6] GSM PAM Schematic

TQM7M5008

(1608)

LOW

HIGH

MODE

DCS/PCS

3 dB

GSM_PA_BAND

GSM

SFSY0030301

18nH

L514

R515

300

R511

18

R512

300

C541

15p

VBAT

C539

3.3p

R516

300

C540

33p

L512

3.3nH

DCS_PCS_OUT

15

5

GND1

GND2

8

10

GND3

GND4

11

GND5

13

GND6

14

GND7

16

17

GND8

7

GSM_IN

9

GSM_OUT

TX_EN

3

4

VBATT

12

VCC

VRAMP

6

U501

TQM7M5008

2

BS

1

DCS_PCS_IN

300

R513

C538 68p

C533

100p

C534 22u

R510

2.2K

18

EFCH836MTDB1

FL501

2G13

G2

5

G3

1

IN

4

O1

R514

L513

4.7nH

GSM_PA_BAND

GSM_PA_EN

GSM_PA_RAMP

DCS_PCS_TX

GSM_TX

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3.4.5 Bluetooth (U403 : BCM2048SKUFBG)

The bluetooth components are an bluetooth module and Antenna. Figure1.7 shows the bluetooth system architecture in the MS25.

3. TECHNICAL BRIEF

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[Figure1.7] Bluetooth system architecture

MSM7200

SG-3030LC

32.768KHZ

Oscillator

BT_REG_CTL

nBT_RESET

FM_IRQ

BT_HOST_WAKEUP

BT_WAKEUP

BT_UART_RXD BT_UART_TXD BT_UART_CTS BT_UART_RTS

BT_PCM_SYNC BT_PCM_IN BT_PCM_OUT BT_PCM_CLK

FM_R FM_L

BT_32KHZ

WLAN_32KHZ

UART

PCM

FM Speaker

VBT_CORE_2.6V

VBT_2.6V

Bluetooth - FM

Combo Chip

Broadcom BCM2048

6X6

NX3225DA

-26MHz

(Xtal)

LFB212G45SG8A166

(Filter)

Bluetooth

Antenna

Connector

FM_ANT

GPIO92

GPIO93

GPIO26 GPIO83 GPIO82

AUX_PCM

Audio

GPIO77

UART1

32KHZ_ON

UART

PCM

FM Speaker

18 Pin

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3. TECHNICAL BRIEF

3.5 Digital Baseband(DBB/MSM7200)

3.5.1 General Description

A. Features(MSM7200)

• Support for multimode operation - GSM/GPRS,EDGE

• The ARM1136-J microprocessor can operate at up to 400 MHz.

• The ARM926EJ-S microprocessor can operate up to 256 MHz.

• Internal 256 MBits stacked DDR memory.

• Java hardware acceleration for faster Java-based games and other applets.

• Supports low-power, low-frequency crystal to enable TCXO shutoff.

• Integrated USIM Controller for direct interface to USIM card

• Software-controlled power management feature

• Integrated Bluetooth 2.0 baseband processor for wireless connectivity to peripherals

• High-speed, serial mobile-display, digital interface that optimizes the interconnection cost between the MSM device and the LCD panel

• USB OTG core supports both slave and limited host functionality

• Integrated wideband stereo CODEC for digital audio applications

• Direct interface to digital camera module with video front end (VFE) image processing

• Vocoder support (GSM-HR, FR, EFR, AMR, W-AMR, and 4GV)

• Advanced 15 x 15 x 1.4 mm, 0.5 mm pitch, 543-pin lead-free CSP packaging technology

• GSM Features

- Voice features (FR,EFR,AMR,HR)

- Circuit-switched data features(9.6K,14.4K,Fax)

• GPRS Features

- Simple Class A operation

- Multi-slot class 12 data services

- CS schemes CS1,CS2,CS3,CS4

• EDGE Features

- EDGE E2 power class for 8PSK

- Simple Class A, multi-slot class 12

- Downlink/Uplink coding schemes (CS1-4, MCS1-9)

• Operation and Services

- LCD & Camera Interface

- USIM Interface

- Dual Memory Buses(EBI1-SDRAM & EBI2-NAND Flash)

- External Memory Interface (Micro SD)

• Data Communication

- Bluetooth

- Slave USB

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3.6 Hardware Architecture

3. TECHNICAL BRIEF

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Figure. Simplified Block Diagram of System

MSM7200

MCP

DDR 1G

NAND 2G

2M AF

2.8î QVGA LCD

Speaker

Receiver

T Flash

- Touch Controller

- Joy Stick

- Send, End, Hot, Power

-Vol. Up/Down

- Camera Shutter

SIM Card

Int. Mic.

Bluetooth

BCM2048

FM Radio

18Pin Cradle

Connector

18Pin Cradle

Connector

PM7540

Battery

USB

Serial Port

RTC Battery

1050mAh

RTR6275

XCVR

RTR6275

XCVR

Switch-

plexer

Switch-

plexer

RF Block

GSM PAM

UART1

SDIO1

GPIO

MIC1

SDIO2

UART2

CAMERA

LOUT/

RCV

EBI1/

EBI2

MDDI

RF

UART3

USB1.1

SBI

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3.6.1. Block Diagram(MSM7200)

MSM7200

CONNECTIVITY

CAMERA

PROCESSING

(Default 8bit

Interface)

GRAPHICS

VIDEO

AUDIO

DUAL MEMORY BUS

ARM1136-J APPS

PLL

APPS QDSP 4

ARM 926ejs

With Jazelle

UMTS, WCDMA,

processor

BT 1.2

processor

Rx ADC

Tx DAC

MP3, AAC,

EVRC, QCELP

AMR, CMX, MIDI

EBI 1 EBI 2

Open GL ES

3D, 2D

MPEG-4

H.263, H.264

Keypad I/F

SD/SDIO1

USB

UART1

UART2 / RUIM1

UART3 / PMIC SBI

Mono

Speaker

Stereo

Headset

MIC

MicroSD

Camera 2M

KEY

PAD

18 PIN

M M I

USB

NAND Flash

2G

SDRAM

1G

LCD

(2.8 inch)

PM7540

GSM/GPRS/EDGE

processor

USIM

4 Bit

JTAG

RF SBI

GPIO

1

8

P

I

N

M

I

MDDI

Modem QDSP4

SD/SDIO2

Figure. Simplified Block Diagram of MSM7200

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Specifications and Main Features

Frequently Asked Questions

User Manual