Sendo M550 Service Manual

M550/M551 Level 3 Service Manual Page1

MM555500//MM555511 SSEERRVVIICCEE MMAANNUUAALL LLEEVVEELL 33

M550/M551 Level 3 Service Manual Page2

Contents:

Section 1. Introduction

Section 2. Repair Precautions

Sendo guidelines for safe and productive repair work.

Section 3. Product Features and Specifications

General features, technical specifications and warranty details for the M550.

Section 4. Product Architecture

Functional block diagrams of the RF and logic circuit architecture. Board layouts are also provided which highlight the main functional areas such as audio, power supplies and RF circuitry.

Section 5. Product Servicing and Rework Guide

Level 3 repair items, recommended rework equipment and guidelines. Also included are the assembly-disassembly instructions.

Section 6. Trouble Shooting

Detailed circuit description and repair information to help debug problems and faults.

Section 7. Software Download

The service centre software download set-up process and its operation.

Section 8. Parts Info

The M550 Parts list including exploded view.

M550/M551 Level 3 Service Manual Page3

Section 1. Introduction

Welcome to the level 3 Service Manual for the Sendo M550/M551. This manual will guide you to repairing the modules used in the Sendo M550/M551 models. The M551 is the United States variant – for GSM 850/1900 Mhz.

This manual will help guide you through all repair aspects of the M550/M551 and provide detailed information on the product.

X102 32 Khz Xtal

M550/M551 Level 3 Service Manual Page4

Section 2

Repair Precautions

M550/M551 Level 3 Service Manual Page5

Important!

Please read the following cautions, notes and warnings

before progressing through this manual or undertaking

any repair action. Remember: SAFETY

FIRST!

AC Main Lead/Power Cord:

Always ensure that ALL AC mains leads used in the repair area are in good condition and checked regularly. Care must be taken not to damage the lead as this could result in fire or electric shock.

Battery Pack:

ONLY use original Sendo supplied batteries and chargers with the M550/M551. DO NOT short the battery terminals together.

Keep the battery pack away from fire and sources of ignition.

Remember to recharge the battery pack after each use.

Before YOU Power up the M550/M551:

• Only switch on the telephone’s power once the test or installation set-up is complete.

• Switching on at the wrong time may result in electric shock or damage to system

components.

• Always ensure that the power is switched off before making connections / disconnection’s.

• It is important to check that the correct DC voltage is applied to the M550/M551 to prevent electrical damage.

M550/M551 Level 3 Service Manual Page6

Component Polarity +/-

Always check the polarity of connections and components before soldering. Particular attention must be paid to I.C’s, diodes, transistors, capacitors and any other semiconductor device that is polarity dependent.

Electrostatic Damage (ESD):

Semiconductor devices are easily damaged by electrostatic discharge. Many of the procedures detailed in this manual involve disassembly of the equipment and therefore handling of the printed circuit boards. To protect these devices from ESD a wrist strap connected to ground must be worn. In addition to this the work surface must be covered with an anti-electrostatic mat, which should also be grounded.

If printed circuit boards are to be stored without being re-assembled into their equipment, then they must be kept in an anti-electrostatic bag.

Grounding:

Each piece of test equipment should be electrically grounded. A third (grounding) pin is provided as a safety feature. Ensure that the electrical outlet also contains this feature.

Cosmetic Protection during Repair Work:

Always ensure that the working surface is kept clean and free from abrasive materials.

The LCD is very susceptible to scratches and damage. It should be covered with clear adhesive vinyl while the equipment is disassembled.

Storage of Faulty Components:

Any components that are replaced due to failure should be kept safely in an anti-electrostatic container. Sendo’s Quality or Research & Development Departments may require them to make quality and reliability investigations.

M550/M551 Level 3 Service Manual Page7

No Fault Found Equipment:

In some cases the reported symptom may not be apparent. You may subject the equipment to a controlled amount of stress, vibration and temperature variation to see if the fault occurs. Care should be taken not to apply excessive stress or vibration or extreme temperature variations as further faults may develop.

Soldering and Disordering :

Fast, accurate and high quality soldering is required to minimise the risk of heat damage to the electronic components. ALL rework must follow methods set out in IPC- 7711 (Rewpork of Electrical Assemblies). NO joint should be touched up more than twice. Wire modifications are not permitted. BGA or fine pitch devices may not be reflowed more than once.

Short Circuits:

Care must be taken to avoid short circuits. Soldering, solder dust, screws, metal clippings, metal wrist watches etc. can cause short circuits on PCBs which may result in component damage.

Test Equipment Calibration:

Your test equipment should be calibrated before use. Frequent calibration is essential to ensure high quality and reliable repairs.

Cleaning:

Before cleaning ensure that the telephone is switched off and disconnected from the power source. Cleaning should be done using a soft dry cloth. If the equipment is heavily soiled a soft cloth soaked in a mild synthetic detergent diluted in water may be used.

Never use benzene or any other chemicals to clean the equipment.

RF Shielding:

M550/M551 Level 3 Service Manual Page8

It is advisable to carry out detailed measurements and repair (in particular RX) in a shielded area to minimise RF interference.

AC Adapter and Battery Charger:

The AC adapter and battery chargers are for indoor use only. Ensure that the devices are not exposed to rain or moisture.

Electrical Safety:

Electrical equipment is hazardous if misused. Any repairs must be carried out with care and only by authorised personnel. Ensure all power sources are switched off and power cords removed before undertaking any repairs.

Hazardous Waste:

The battery pack, if incorrectly disposed of, is an environmental hazard. It must be disposed of in accordance with the regulations of the country concerned. Never dispose of the battery pack in fire or water.

Confidentiality:

The circuitry within this equipment contains several components that are regarded as company confidential. Only use Sendo authorised parts as replacements.

RF Injury:

To avoid RF injury, direct exposure to radio frequency energy should be avoided. In particular, exposed parts of your body (especially the eyes and face) should not come into contact with the antenna while the equipment is transmitting.

M550/M551 Level 3 Service Manual Page9

Storage Conditions:

It is recommended that the following storage conditions should be avoided to prevent damage to the equipment: Dusty. Humid.

Near to magnetic equipment.

In direct sunlight.

Ventilation:

Repair areas should be well ventilated and fume extraction systems should be installed where necessary. Potential hazardous substances are solder fumes, flux, alcohol etc.

PCB Handling:

It is recommend that cotton or latex gloves are worn during repair work. This is to protect your hands from chemical contamination and to protect the PCBs from fingerprints and humidity.

SIM Card:

• Do not bend.

• Clean by using a soft dry cloth.

• Please note that a modified SIM card will be required to perform conducted rf

measurements via the rf switch. See section 5. Product Servicing and Rework Guide.

M550/M551 Level 3 Service Manual Page10

Section 3

Product Features and

Specifications

M550/M551 Level 3 Service Manual Page11

PPrroodduucctt DDeessccrriippttiioonnss

 M550 IMEI TAC code: 35188400 (M551:001031A)

 Model Type: SND550/SND551

NNeettwwoorrkk SSeerrvviicceess

 Dual Band E-GSM 900 / GSM 1800 - M550  Dual Band GSM 850 / GSM 1900 - M551  Automatic switching between bands  Manual and automatic network selection  HR / FR / EFR codec for GSM 900 / 1800  M551 includes AMR FR and AMR HR

DDiimmeennssiioonnss aanndd WWeeiigghht

Length (a)

Width (b) 19.6mm at widest point

Depth (c) 45mm at thickest point

82mm at longest point

t

a

Weight 77g

Volume 68cc

PPoowweerr MMaannaaggeemmeennt

 Talk Time: Up to 180-400 mins*  Standby Time: Up to 120-300 hours*  Game-Play up to 3 hours*

 Sim Type:  Charging time: <2 hours  Battery: Li-Ion cell - 650Ah, 3.7vdc  Linear charger (240v Euro plug, 240v UK plug, 220v China plug, 110v US

plug or 220v Australian plug)

* Battery life is Network dependent; variations may occur.

The M550/M551 works closely with the network and the standby and talk times achieved depend upon this. In particular the location of the HHP within the network, the type of SIM, reception of area messages, the use of

Micro 3V or 5V SIM

t

c

b

M550/M551 Level 3 Service Manual Page12

Full Rate speech or Enhanced Full rate speech and other factors will affect both standby and talk times.

MM555500 CCoorree FFeeaattuurrees

s

Product Features

 Clamshell design with internal antenna  Size: 77g, weight: 68cc  Dual display, outer: reverse video, 96x64 pixels  Inner colour display – up to 4096 colours  Customizable colour themes  On phone dynamic memory-up to 500 phone book entries  Colour EMS  Wap 1.2.1 colour browser and GPRS class 8  Colour games  Tegic T9 text input, built in SMS chat and SMS templates  Animated graphics and sound  Dual Band (M550:E-GSM 900/1800, M551:GSM850/1900  Stand by time up to 180-400 hours*  Talk time up to 120-300 mins*  Gameplay up to 3 hours*

*talktime and standby times depend upon network conditions and the way you use the phone.

M550/M551 Level 3 Service Manual Page13

WWaarrrraannttyy DDeettaaiills

s

Limited Warranty

Sendo International Limited (“Sendo”) warrants, subject to the exclusions and limitations set forth below, that your cellular phone, battery and accessories (collectively “Product”) is free from defects in materials and workmanship according to the following terms and conditions:

1. The limited warranty for the Product commences on the date of purchase and continues for a period of one

(1) year from that date. Upon request from Sendo, you, (the “Consumer”) must prove the date of the original purchase of the Products by dated itemised receipt.

2. The limited warranty extends to the original purchaser of the Product, the Consumer, and is not assignable

or transferable to any subsequent purchaser or user.

3. The warranty extends only to Consumers who purchase the Product in the market for its intended sale.

4. During the limited warranty period, Sendo will repair, or replace, at Sendo's sole option, any defective parts, or any

parts that will not properly operate for their intended use with new or refurbished replacement items if such repair or replacement is needed because of a malfunction or failure of the Product during normal usage. No charge will be made to the Consumer for any such parts. Sendo will also pay for the labour charges incurred by Sendo in repairing or replacing the defective parts. This warranty does not apply to any damage or failure to operate caused by use of the Product other than in accordance with the instructions contained in the User Manual, or for periodic maintenance or repair due to normal wear and tear. Sendo's limit of liability under the limited warranty shall be the actual cash value of the Product at the time the Consumer returns the Product for repair, determined by the price paid by the Consumer for the Product less a reasonable amount for usage. Sendo shall not be liable for any other losses or damages. These remedies are the Consumer's exclusive remedies for breach of warranty

5. The warranty will be invalidated if any of the following circumstances are applicable:

a) The Product has been subject to abnormal use, abnormal conditions, improper storage, exposure to

moisture or dampness, unauthorized modifications, unauthorized connections, unauthorized repair, misuse, neglect, abuse, accident, alteration, improper installation, or other acts which are not the fault of Sendo, including damage caused by shipping.

b) Physical damage to the surface of the Product, including scratches or cracks in or to the outside casing or

Liquid Crystal Display, or damages caused by dropping the Product.

c) The Product has been damaged from external causes such as liquid, water, collision with an object, or from

fire, flooding, sand, dirt, windstorm, lightening, earthquake or damage from exposure to weather conditions, an Act of God, or battery leakage, theft, blown fuse, or improper use of any electrical source, damage caused by computer or internet viruses, bugs, worms, Trojan Horses, cancelbots or damage caused by the connection to other products not recommended for interconnection by Sendo.

d) The Product has been altered or repaired by anyone other than an authorised Sendo service centre or if it

has been used with unapproved accessories or other ancillary items.

e) For adaptations or adjustments made to the Product to comply with local standards in any country other than

one for which the Product was designed and manufactured.

f) Loss of integrity of any user data stored in the Product or any storage device used in conjunction with the

Product at any time

g) The Sendo authorised service centre was not advised by the Consumer in writing of the alleged defect or

malfunction of the Product within fourteen (14) days after the expiration of the applicable limited warranty period.

M550/M551 Level 3 Service Manual Page14

h) The Product serial number plate or the accessory data code has been removed, defaced or altered.

i) The defect or failure to operate was caused by the defective function of the cellular system or by inadequate

signal reception.

6. Any implied warranty of satisfactory quality, merchantability, or fitness for a particular purpose or use, shall be

limited to the duration of the foregoing written warranty. Otherwise, the foregoing warranty is the Consumer’s sole and exclusive remedy and is in lieu of all other warranties, express or implied. Sendo does not warrant uninterrupted or error free internet or data connections. Sendo shall not be liable for special, incidental or consequential damages, including but not limited to, loss of anticipated benefits or profits, loss of savings or revenue, punitive damages, loss of use of the product or any associated equipment, loss of data, cost of capital, cost of any substitute equipment or facilities, downtime, the claims of any third parties, including customers, and injury to property, resulting from the purchase or use of the product or arising from breach of the warranty, breach of contract, negligence, strict tort, or any other legal or equitable theory, even if Sendo knew of the likelihood of such damages. Sendo shall not be liable for delay in rendering service under the limited warranty, or loss of use during the period that the product is being repaired or loss of data.

7. Some jurisdictions do not allow limitation of how long an express or implied warranty lasts and so the one year

warranty period referred to above may not apply, to you, the Consumer. Some jurisdictions do not allow the exclusion or limitation of incidental and consequential damages and so to the extent that such limitations are not allowed, the above limitations or exclusions may not apply, to you, the Consumer. This limited warranty gives the Consumer specific legal rights and the Consumer may also have other legal rights under the legislation of some jurisdictions. These legal rights vary from jurisdiction to jurisdiction and are not prejudiced by anything contained in this limited warranty. It also means that in some jurisdictions our responsibility to you the Consumer may be more extensive than in other jurisdictions.

8. The Consumer shall take the following steps to make a claim under this limited warranty:

a) Please do not ship the Product for service without first contacting the nearest Sendo Authorised Service

Centre.

b) Contact information for the world-wide network of Sendo authorised service centres is available at

www.sendo.com

c) If the Product qualifies for in-warranty service, the Consumer must prove the date of the original purchase of

the Products by a dated proof of purchase.

d) Back up all data. If the Consumer has sensitive information stored on the Product copy it to another device

and delete it from the Product before repair.

e) The Consumer must ship the Product prepaid and insured. Expenses related to removing the Product from

an installation are not covered under this limited warranty.

f) If the Product is returned for service and the Product is deemed out of warranty under the terms and

conditions of this warranty, the Consumer will be notified and given an estimate of the applicable charges. If the estimate is refused a minimum service fee for collection, inspection and quotation of said product would be due.

9. Subject to any more extensive legal rights granted to the Consumer by law of the Consumer’s jurisdiction, Sendo

neither assumes nor authorizes any authorised service centre or any other person or entity to assume for it any other obligation or liability beyond that which is expressly provided for in this limited warranty including the provider or seller of any extended warranty or service agreement.

10. This is the entire warranty between Sendo and the Consumer, and supersedes all prior and contemporaneous

agreements or understandings, oral or written, and all communications relating to the Product, and no representation, promise or condition not contained herein shall modify these terms.

11. This limited warranty allocates the risk of failure of the Product between the Consumer and Sendo. The allocation

is recognized by the Consumer and is reflected in the purchase price of the Product.

12. Diagnostic instructions and other service information is available free of charge at www.sendo.com

out of warranty repair costs and charges is available at www.sendo.com

. Information on

.

M550/M551 Level 3 Service Manual Page15

Warranty Details

Identifying the manufacturing date on a unit.

EXAMPLE,

First LETTER = YEAR Second LETTER = MONTH

DD = 2003, April

NOTE:

THE CODES HAVE ONLY BEEN ISSUED ON MANUFACTURED UNITS AFTER SEPTEMBER 2001.

M550/M551 Level 3 Service Manual Page16

The Table below shows the manufacturing dates and their codes.

WWaarrrraannttyy TTaabbllee

CODE MANUFACTURED DATE OUT OF WARRENTY END OF

BI

BJ

BK

BL CA CB CC CD CE

CF CG CH

CI

CJ CK

CL DA DB DC DD DE

DF DG DH

DI

DJ DK

DL EA EB EC ED

EE

EF

SEPT 2001 NOV 2002

OCT 2001 DEC 2002 NOV 2001 JAN 2003 DEC 2001 FEB 2003

JAN 2002 MAR 2003 FEB 2002 APR 2003

MAR 2002 MAY 2003

APR 2002 JUNE 2003

MAY 2002 JULY 2003

JUNE 2002 AUG 2003

JULY 2002 SEPT 2003

AUG 2002 OCT 2003

SEPT 2002 NOV 2003

OCT 2002 DEC 2003 NOV 2002 JAN 2004 DEC 2002 FEB 2004

JAN 2003 MAR 2004 FEB 2003 APR 2004

MAR 2003 MAY 2004

APR 2003 JUNE 2004

MAY 2003 JULY 2004

JUNE 2003 AUG 2004

JULY 2003 SEPT 2004

AUG 2003 OCT 2004

SEPT 2003 NOV 2004

OCT 2003 DEC 2004 NOV 2003 JAN 2005 DEC 2003 FEB 2005

JAN 2004 MAR 2005 FEB 2004 APR 2005

MAR 2004 MAY 2005

APR 2004 JUNE 2005

MAY 2004 JULY 2005

JUNE 2004 AUG 2005

M550/M551 Level 3 Service Manual Page17

Section 4

Product Architecture

M550/M551 Level 3 Service Manual Page18

r

Section.1: M550 Product Structure – Exploded view

Outer Lens Assy

Screw (4pc)

Outer Ring Assy

LCD Module

FPC

Front Hsg Assy

Keypad

Metal-dome

Mic Gasket

Inner Hsg Assy

Lens Assy

Hinge

Battery

Holde

SIM

PCBA

Screw (2pc)

Battery

Battery Cover

M550/M551 Level 3 Service Manual Page19

Logic circuit Architecture

Part a: Audio Circuits and SIM Interface

IOTA

IC200

VOICE BAND SERIAL PORT

K3

G5

H5

F5

VOIC BAND CODER/ DECODER

J9

J10

E

SIM_IO

SIM_CLK

SIM_RST

K9

C7

G7

J8

J7 H7

BB_VCLK

BB_VFS

BB_VDX

BB_VDR

(Buzzer)

BB_EARP

BB_EARN

(Ear Piece)

SIM_VCC

IO VDD

CLK

RST

BB_MIC_REF_P

BB_MICP

BB_MICN

BUZZ_EN T401

BB_SIM_IO

BB_SIM_CLK

BB_SIM_RST

SIM Reader (X402)

BB_AUX_MIC

MIC

N12

M13

N13

P14

CALYPSO

K7

IC100

X200

(Audio Jack)

AUXOP

3

2

Part b:

M550/M551 Level 3 Service Manual Page20

Part b: Logic Circuit Block Diagram

CHGR

IC200

IC100

(X102 – 32Khz)

The main functional blocks of Calypso (IC100) are:

• ARM Megamodule (ARM7TDMIE)

• DSP Megamodule (S28C128)

• Memory Interface & Memory Protection Unit

• Interrupt Handler (INTH)

• Clock Management (CLKM)

• Timers

• General Purpose IO (ARMIO)

• UART – IRDA and UART – MODEM

• UWire Interface (UWIRE)

• I2C Master Serial Interface (I2C)

• Serial Port Interface (SPI)

• Pulse Width Tones (PWT)

• Pulse Width Light (PWL)

• Light Pulse Generator (LPG)

• Debug Unit (DU)

The main functional blocks of IOTA (IC200) are:

• Automatic Frequency Control Unit

• Auxiliary Drivers

• Automatic Power Control Unit

• Baseband Codec

• Back up Battery Switch, Battery Charger Control

• Baseband Up / Down Link, Baseband Serial Port

• Clock Generator

• LDO Voltage Regulators, Voltage Reference, Power Control

• Monitoring Analogue to Digital Converter

• SIM interface

• Time Serial Port, Test Access Port

• Microcontroller Serial Port

• Voice band Codec

• Voice Serial Port

Flash

SRAM

IC300

M550/M551 Level 3 Service Manual Page21

A

Section.2: Radio Architecture

Part a: Receiver Block Diagram

IC500 RF Switch

SW

saw

6 7 9 10

PCS GSM

20 19 22 21

saw

LPF

ADC

1 2 ION IOP 12 11

Channel filter

DAC

IC600

Demodulator

HPF

LPF

Π/2

IC601

IF Mixer

IOP ION CLKP CLKN

100 KHz

NT

13 RF_LON 23

12 RF_LOP 24

7

RF_CLK_13M

4 5 2 3

D9 D10 C9 C10

003

IC100

CALYPSO

PDNB RF_TPU_DATA_OUT (SDO)

3

RF_TPU_DATA IN (SDI)

IC602

Synthesiser

RF PLL

7

3

IICC660033

((1133MMhhzz))

RF_AFC

IICC220000

IOTA

RF_IP RF_IN

RX = I+Q

RF_QP RF_QN

M550/M551 Level 3 Service Manual Page22

)

part b: Transmitter Block Diagram

RF_PA_CTL_EN 3

QP QN IP IN

VCCOUT

9 10 11

7 6 1

VRAMP

÷1 DCS ÷2 GSM

(IC200)

TX_VCO_GSM TX_V CO_PCS

IC700

25 24

IC601

LPF

∅detector

LPF

OFFSET PLL

÷

TX = I+Q

IICC220000 ((IIOOTTAA))

EGSM_PA_TX

PCS_PA_TX

Power Amps

(PA

13 RF_LON 24

14 RF_LOP 23

10 IF_ LON 27

11 IF_ LOP 28

IOP ION CLKP CLKN

M550/M551 Doc SP11498 Rev:01 Aug03

1

11

IC500 RF Switch

LPF

HPF LP F

ANT

RF_AFC (IC200)

MF501

IICC660033

13Mhz Reference

RF PLL

IC602

IF PLL

3

IICC660000

9

2

V

CXO_13MHZ

3

7

PDNB RF_TPU_DATA_OUT (SDO) RF_TPU_DATA IN (SDI)

M550/M551 Level 3 Service Manual Page23

)

Section.3: M550 Functional Areas

Part a: Keypad, MIC and Backlight Area’s

In this section are shown the locations of the main keypad, backlight and Mic locations.

Side.1

X404: MIC

Keypad Area (Shown without Metaldome sheet fitted

MF_110: Flip detect contact pad

Backlight LED’s (D402-D410)

M550/M551 Level 3 Service Manual Page24

p

Section.3: Functional Areas – Cont’d

Part b: RF and Logic functional blocks

Here are shown the main functional parts of the logic and RF circuits.

Baseband Circuitry area (in blue)

Side.2

X402 - SIM Interface

X501 – Antenna

RF Switch

RF Circuitry areas (in grey)

X403 Connector (Connects PCB to LCD Module via *FPC).

IC407 Sound Synthesiser

PA

IC504 - Antenna

IC700 – TX Power Amplifier

and associated circuit.

X400 - Battery Connector and DC

ower supply

Non-replaceable Parts IC100 “Calypso” (BGA-Underfilled) IC200 “IOTA (BGA –Underfilled) IC301 Flash/SRAM – Underfilled) IC405 LCD Driver IC700 Power Amplifier Shielding Frames (BB & RF)

X200 - Audio Jack and

charging socket.

M550/M551 Level 3 Service Manual Page25

IC603 13Mhz Clock

Main RF Circuit devices:

IC500: TX/RX path switching IC IC501: RF 2.8V POWER SUPPLY (VCC_2V8_RF) IC600: RX Demodulator IC601: IF+RF Modulator and Mixer IC602: IF+RF Synthesisor (PLL- Phase Locked Loop) X501: Mechanical rf switch IC603:13Mhz Clock IC502: GSM1800 Rx band pass filter IC503: GSM900 Rx band pass filter IC504: Antenna

X102 32 Khz Xtal

Page:26

M550/M551 Level 3 Service Manual

Section 5

Product Servicing

Page:27

M550/M551 Level 3 Service Manual

5.1 Level 1-2 Repair Items

Administration Checks

- Warranty Check

- Phone and Accessories

- DOA Filter Analysis (if required)

- Checking Fault report from customer

Level 1

- NFF

- SWAP

- Outer Bezel

- Inner Bezel

- Battery Cover

- Charger

- Battery

- Accessories

Level 2

- Labels

- Software Upgrade/Blocked Units

- Battery Holder

- Inner Housing

- Outer Ring

- Front Housing

- Keypad

- Board to Board FPC (Flexible Plastic Connector)

- Shielding can covers (Baseband+RF)

- Hinge assembly

- Metaldome

- Mic Gasket

- LCD Module (Replacement only)

- PCB cleaning

- Discreet components which just require soldering to replace

o Charger Socket o Sim Connector o Battery Connector o Mic o Buzzer, Vibrator and Earpiece (Speaker) o Backlight LED’s o Antenna

Level 3

- Components that need replacing after test equipment de-bug analysis

- Internal DAC level calibration, setting internally in phone

- Re-programming IMEI – Security

NOTE : Level 3 repair is restricted on the SND550 as some IC’s are under filled.

Page:28

M550/M551 Level 3 Service Manual

5.2 General Quality Guidelines for Rework

The following guidelines should be followed when either reworking joints or replacing electronic parts.

• All rework must follow the methods described in part 5.3b – “Prefered rework methods” and to standard IPC-7711 (Rework of Electric/Electronic Assemblies).

• No joint may be touched-up more than twice.

• Wire modifications are not permitted.

• Any BGA devices on M550, which are underfilled must not be reworked or

replaced.

5.3a Recommended Equipment for Repair

Rework Tools

Soldering Iron: - Lockable temperature-regulated soldering iron station.

E.g. JBC AM6000, Weller WSD80 or Metcal MX-500

Hand Tweezers: - ESD safe flat rounded point Solder Braid: - Multicore AA or Chemtronics 60-2-10 (size #2) Solder: - Tin/Copper Lead Free (0.5 – 1.0mm diameter) Flux: - Cobar 390RX Flux Applicator: - Boncote BON-102 Torque Driver:- Calibrated to 10Ncm (+/- 1cNm) with bit Posidrive size “0” Protective Gloves:- Disposable Latex gloves / Finger Cots. Cover opening Tool* - Available from Sendo.

Cover Opening tool

Page:29

Adaptor fitted to battery eliminator.  RF Note: Can only be used with  battery eliminator.

Gold Guard Pen:- (for cleaning all contact pads) as below:-

M550/M551 Level 3 Service Manual

This item is available from: RS Components Ltd (Part no: 298-7779), Website:rswww.com

Electronic Equipment

Digital Multimeter (DMM) 5V DC Power Supply GSM Test Set PC with Windows XP or 2000

Battery Eliminator* :- For software downloading and powering unit. Can also be used

to perform RF measurements**.

**RF adaptor (optional) must also be fitted to perform measurements).

* Please contact Sendo for Details of aquiring these items

Page:30

M550/M551 Level 3 Service Manual

Leaded RF adaptor fitted with support collar*:- for performing RF measurements of

M550/M551 if using standard battery. Plugs directly into rear of M550/M551.

Collar fitted to RF adaptor

Leaded RF adaptor “without" Collar

RS232 Interface Box with 9 VDC power supply and serial cable*

Regulated 9vdc Power Supply for RS232 interface box.

Used to provide DC power to the RS232 Interface Box.

UK Type

EU Type

Sendo M550 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual