Mobile Phone Common damages comes with Battery

When Damage Mobile phone Battery you will be able to see lot of faults in your phone. Then you must change your Battery for solve that faults but if you cant identify about that faults which are comes with Battery definitely you will try to repairing your phone using other methods. Because of that sometimes your phone will be dead.Therfore you must know about that faults and how can you solve its. Carefully read following notes step by step and identify about all damages which are comes with Battery.

What is Memory Effect

Memory Effect is that if battery is repeatedly only partially discharged before recharging , battery forgets that it has the capacity (cells) to furhter discharge all the way down. If you fully charge your mobile phone battery and then use only 75% of its capacity before the next recharge , eventually the battery will become unaware of its extra % capacity which has remained unused.

The battery will remain functional , but only at25% of its original capacity. When you do same thing step by step remain functional which is in your battery will not be worked and that cells will be dead.After that we can say that battery has been memory effected.


What are the faults comes with Memory Effect

Power On failure

No Charging

Signal Drop

When you power on with sim card, Power off other wise ok

When signal come phone will power off

When make a call Battery empty or powe off

Battery life time will be reduced

Battery will charge quickly

Battery will heat

Insert sim card problem

unable to run some applilcation in your phone

Software problems

Etc...........

Reason and solution for above faults (if its are Battery faults)

Power On failure:
When Battery Voltage less than 3.7V Phone will be power on failure. You must Recharge your Battery or replace a new battery. If you can connect your phone to power supply machine then you will be identify this faults easily.

When your Battery Voltage less than 1.9V( or some thimes it can be2.4V ). You must boost your battery or high charge( do it correctly like this , give 10 pulse for battery conectors using 6V. Warning. used correct voltage and 30 seconds for each pulse otherwise it will be damaged). 

Warning : Specially this damage is come with Hardware parts. firstly you can connnect to power supply and identify reason for that fault.

Signal Drop :

Generally Signal circuits want high voltage( around 4V ) for doing its job properly. But if your phone Battery is damaged or memory effect that circuits cant get this voltage continuously because of that you can see signal drop in your phone.

When you replace a good battery for old one this faults will be solved.

Warning : Specially this damage is come with Hardware parts. firstly you can connnect to power supply and identify reason for that fault.

When you power on with sim card, Power off otherwise ok

When signal come phone will power off
When you Power on with sim card Signal circuit will worked and its want good voltage source. If your Battery is memory effect , it will be unable to give power for signal circuit and Power ic. Therefore Phone will be shut down. when you replace new battery for your phone it will be ok. Warning : Specially this damage is come with Hardware parts. firstly you can connnect to power supply and identify reason for that fault.

When make a call Battery empty or powe off

When make a call Signal circuit and RF units are working with full capacity and also that circuits want high volatge for working. If your mobile phone battery is memory effect it will be unable to supply that voltage Because of that your phone will be shut down. 

when you replace a good battery for old one that fault will be solved. 

Warning : Specially this damage is come with Hardware parts. firstly you can connnect to power supply and identify reason for that fault.

Battery life time will be reduced
Battery will charge quickly
Battery will be heat
Because of memory effect your mobile phone battery have damage cells therefore it hasnt full capacity so when you plug in charger it will be battery full quickly. Not only that but also it will be heat and life time will be reduced.

When you change Battery you can solve that faults easily. Warning : Specially this damage is come with Hardware parts. firstly you can connnect to power supply and identify reason for these faults.

Insert sim card problem
Minority you can see insert sim because of BSI terminal not connect with PCB Battery pin. If your battery is a exploit one or damage one you must change it. But specially , Majority this fault is come with hardware damage.

unable to run some applilcation in your phone
Software problems 

When you run any application in your phone it will take high voltage more than stand by time. If your battery is memory effect , it will be unable to supply that voltage therefore you will be unable to run that software or application in your phone. 

Please change the battery and try to do it again , if it is come with battery definitely it will be worked properly.

Warning : Specially this damage is come with Software faults. firstly you can connnect to power supply and identify reason for

This note help to understanding about memory effect and what are ther faults comes with battery.Notonly that but also you can identify how you can solve that faults correctly. Try to Be a good technician.

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Kinds of Faults in Mobile Phones

There are Main Kinds of Faults in Mobile Phone which we can see generally.

Mobile phone is an Electronic Device and also it has been included a Software. Because of that this electronic device have lot of electronic parts ( IC, Capacitor, Resistor, Diode, Coil , Relay, Transistor,... etc) and settings for main software not only that but also these electronic parts or Software Settings can be damaged or changed.

Therefore your mobile phone may be damaged. A typical mobile phone has two main kinds of faults as Hardware and Software faults. But some software faults are comes with settings so we can divide that faults as following main parts.

1. Hardware: When Damage any Hardware parts ( Electronic parts or PCB )
2. Software: When Damage Software which is in mobile phone.
3. Settings : When change mobile phone settings as unconditional

Hardware Faults
These faults are related to PCB , Batteries and any other electronics parts fault. There are example for understanding about what are the hardware faults.

No Signal

Battery Empty

Dead set condition

Auto Restart

No Charging

No Display or Display lights

keypad faults

Display other problems

Insert Sim Card

Low signal

No Network Access

Call Drop

Phone off when make a call

Voice fautls

Ringer fautls

Earpiece faults

Mic faults

Auto turn off

Vibrator faults

............ Etc..

Software Faults
These faults are related to Software which is in mobile phone.Every mobile phone has a OS. When it is damaged you must flash or format your phone. There are example for understanding what are the software faults.

Dead set

Not Charging

Test Mode

Contact Service

No Signal

Auto Restart

Some Applications not work

When you send SMS or MMS phone will restart

Camera Not work

Booting Problems

Sim not valid or Insert correct sim

.............Etc..

Setting Faults
These faults are related with mobile phone settings. If you changed your phone settings as unconditional and also virus can change that settings as harmfull then following faults can be seen in your mobile phone.

Call Divert

No network

Only incoming call

Auto Restart

Battery empty

Stuck your phone

Phone is slow

When make a call phone will restart or off

Sim Lock

Unable to send SMS

Some Application not work properly

Security Code problems

Black list problems

..............Etc..

When you try to repair damage phone firstly you want to know what is the damage and how can repair it. when you read this blog you can identify mobile phone faults and how you can solve it. This is the first step for it " Understanding What are the kinds of Faults in Mobile Phones.

Try to be a good Mobile phone reapiring technician. Good Luck to you.

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Cellphone Repair Tools and Test Equipments

Cellphone Repair Tools and Test Equipments

when you are doing mobile phone repairing you have to get neccessary tools for that. here are many different variety and Cellphone Repair Tools. you can get these tools from your base town or some electronics shop. Not only that but also A lot companies offers online purchasing for such certain tools for beginning into business. You can choose which is which for such certain product.

Basically these are the primary tools for you have to buy.

* Multi-Tester - To measure Voltages, Currents and Resistance in electronic components.

* Screwdrivers - To loosen the phones screws.

* Tweezers - To hold and pick small cellphone component parts.

* Soldering iron - To solder / resolder electronic parts.

* Soldering lead - To bonds Electronic components.

* Soldering Flux and Paste -To tightened soldering quality.

* BGA Rework station - Applied Heat to soldering, remove and replaced parts and IC chips.

* Re balling Kits - Tools for reballing IC bumps, this composed of Stencil plates, Ball Leads and Spatula

* DC Regulated Power Supply- Used to substitute battery voltage when working on hardaware troubleshooting.

* Flashing and Unlocking Device- it is Software Tools that used to unlock and flash mobile phone programmable circuits.

* Cables and Wires - Used as an Interface from PC to cellphones when working on like flashing, unlocking and jailbreaking

Soldering and Desoldering Tools.

*Soldering Iron

A soldering iron is a hand tool most commonly used in soldering. It supplies heat to melt the solder so that it can flow into the joint between two workpieces.

A soldering iron is composed of a heated metal tip and an insulated handle. Heating is often achieved electrically, by passing an electrical current (supplied through an electrical cord or battery cables) through the resistive material of a heating element. Another heating method includes combustion of a suitable gas, which can either be delivered through a tank mounted on the iron (flameless), or through an external flame

*Soldering Leads
Soldering leads are used for joining or bonding two electronics components.

*soldering paste and flux
A Flux is a chemical for cleaning and dissolving the oxide skin off the metal.

*Soldering Wick
A Solder wicks are use for removing solder for any solder joint and typically oxygen free copper, which has been treated with a rosin solder flux.

*SMD Rework station manually and IRDA
Surface Mounted Divice (SMD) Rework stations are used to replace, re-balling Ball Grid Array(BGA) and remove chips or SMD components.

Measuring Tools

*Multimeter Analog and Digital
Multimeter is a tool for measuring value of Resistance(ohm) ,current flow (Amperes AC, DC),Volatage(AC ,DC) and more other measurments.Specially we want to use this tools for recognizing sort or open circuit in your phone board.

*DC Power supply Analog or Digital
DC Power Supply is a electronic machine for us as a mobile phone battery not only that but also we can check PCB( how many amperes take the PCB when standby mode, dead mode, call mode or off mode) using this machine.

Cleaning PCB board or other equipments

*Small paint brush
When we want to clean PCB we must to do eliminate and wipe dust on PCB therfore we can use brush and sponge for it.Don't use brushes which have made electrostatic.

*Sponge

*Anti static liquid or thiner
When we clean the PCB we want to remove oxide, dust and unnecessary parts on PCB. Specially at this time we can use anti static liquid for this. But a lacquer thinner is a substitute to anti static cleaner and commonly and widely used by many technician's.

*Ultrasonic Cleaner(PCB cleaner)
If you cant clean your PCB manuallly there is a machine for it.Ultrasonic Cleaner- A machine that cleans by using a fluid that is vibrated at 20,000 cycles per second. When the vibration speed rises above the ultrasonic frequency level, bubbles explode and generate strong power, cleaning the surfaces and cavities of hard-to-clean objects.

Reballing Kit
If any BGA has weak or broken balls we want to Reball it.There are Reballing kits we can use.The process is that they just remove the entire solder balls and flattened out the entire bump terminal then replace the chips again.

*BGA Solder Balls
We can use BGA Solder Balls for broken or weak balls of the chip.

*Reballing Stencils
Using this Stencil we can get properly align the solder ball on every bumps of the chips.

*Spatula
We can use Spayula to gathered the solder ball on each holes of the Stencil plates.

check this all equipments and firstly you must training how these tools use and what are the important things. Good Luck and try to be a good technician.

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Introduction about Mobile Phone IC's( Integrated Circuits )

Integrated Circuits

There are Complete notes about Main IC's in mobile phones and How can you identify its. Not only that but also you can get a real idea about mobile phone damages or faults which are comes with IC. Specially there are three main type IC s in mobile phone. These are

1. Pin IC
2. Path IC
3. MBGA ( Micro Ball Grid Array )

Pin IC

Integrated Circuits are complex circuits which have been etched onto tiny chips of semiconductor. When we think about Pin IC, The chip is packaged in a plastic holder with pins which will fit the holes on stripboard and breadboards. Very fine wires inside the package link the chip to the pins.

How Can we numbering the Pins in IC
These pins are which is in Pin IC have been numbered for finding more 100% correctly details about its circuitit. Number 1 is which we can see when we checking anti-clockwise around the IC (chip) starting near the notch or dot.

You can mount and unmount or replace these IC s using SMD rework station. However when you replace like this IC you must mount all pin to the PCB and do not short circuit.Specially Latest mobile phones have not like this IC s. But when you training to mount and unmount these Ic s then you will be able to replace chinease phone display , Switches ... etc.

Path IC
When you check your mobile phone PCB , you will be unable to find these ICs quickly .But when you unmount these ICs you can easily identify thats. following images will be helpfull for undersanding about its ecternal appearance.

Majority ,Power Amp and Antenna Switch are come as this type of IC.However you can mount and unmount easily using SMD Rework station. But unfortunately we can see only two or three ICs on common mobile phones.

MBGA( Micro Ball Grud Array)The BGA is descended from the pin grid array (PGA), which is a package with one face covered (or partly covered) with pins in a grid pattern. These pins conduct electrical signals from the integrated circuit to the printed circuit board (PCB) on which it is placed. In a BGA, the pins are replaced by balls of solder stuck to the bottom of the package.

These solder spheres can be placed manually or with automated equipment. The solder spheres are held in place with a tacky flux until soldering occurs.The device is placed on a PCB with copper pads in a pattern that matches the solder balls. The assembly is then heated, either in a reflow oven or by an infrared heater, causing the solder balls to melt. Surface tension causes the molten solder to hold the package in alignment with the circuit board, at the correct separation distance, while the solder cools and solidifies.(wikipedia)

You can use Infared , Laser or manual SMD rework station for removing or mounting for BGA. When you have remove BGA IC firstly you want Clean PCB surface and Reballing IC and pcb surface.

After Reballing you can see IC and PCB as following

Finally you can mount new or reballed IC using Laser, Infared or manual SMD Rework stations.

Specially Before you Remove your BGA IC firstly try to solve damage soldering or heating. then you can remove that damage IC and try to replace new one. When you replace that IC some times your phone will be short circuit , if it is short circuit never try to Switch on and try to Soldering otherwise replace again it. However you want get a good experience for doing that therefore you can practice with dead or damage phones. 

his note will help you to understand about Main IC type in mobile phones and about its important. Whatever Try to be a Good Technician. Good Luck 2 U.

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Mobile Phone Hardware Repairing ( about faults comes with IC )

Mobile Phone Hardware Repairing ( about faults comes with IC )

We can divide all Mobile phone damages as Hardware , Software and Settings faults. when we think about hardware damages or faults mainly we want to know what are the main ICs and faults comes with IC. Old phones had ICs more than latest phones. However when you get complete idea about that ICs then you will be able to find solution for damages in your phone properly.Check following list of ICs and try to understand about that faults.

Power Amp

Antenna Switch

RF Processor (hagar IC)

Power IC

CPU

Charging IC

Flash IC ( ROM or EEPROM)

Oscillator (VCO)

Sim IC

Key Pad IC

LCD Light control IC

Power Amp
This is a very important IC for Transmiting signal(Tx) in your phone. This IC is work as a Tx amplifier and it get high voltage directly from the battery.When it is damage we can see following faults.

Signal Drop

No Network or Access

Battery low quickly

Cant make a call ( Tx not work properly )

Power on failure

Phone will heat

Antenna Switch
Antenna switch is help to filtering frequency Bands as 900Mhz , 1800Mhz and connect Rx ,Tx( Receiver and Transmitter). Therefore when damage this IC we can see faults as following.

Signal Drop

No Network found

Some Frequency band are not worked properly

RF Processor ( Hagar IC)
RF( Radio Frequency ) Processor is a main IC in your phone PCB. This IC is used for processing Rx and Tx signal ( for Modulating and Demodulating). sometimes it make a low frequency clock signal is used to start CPU functions. Therefore when damage this IC we can see faults as following.

Power on failure

Signal drop

No network

Caller drop

Rx or Tx or both are not work properly

Battery empty quickly and phone will heat

Power IC
Power IC distribute current to all the components and IC in PCB. we can think that, it is work as voltage regulator therefore if it is worked not properly phone will not be power on. specially we can see some times some applications are not worked because of Power IC is damage.(when power ic not distribute current for circuits that circuits are not worked).

Power on failure

Battery empty quickly

Phone will heat

Insert Sim

No Charging

Some applications are not worked properly

Auto Restart

CPU (Central Process Unit)
Central Process Unit is the brain in your mobile phone and controller all commands which we have given. Specially this IC check flash IC before booting mobile phone after that it will give command to Power IC. When it damages we can see following faults.

Power on failure

Auto Restart

Commant not accepted

KeyPad not working

Battery empty

Phone will be heat

Phone will stuck

Charging IC
This IC is not a common IC among latest phone. However it is used for controlling charging.when it is damage we can see charging faults like these No charging , Not Charging , Auto charging or Charger not support( Bad contact charger). Nowadays Power IC ( UEM) working as a charging controll IC.

Flas IC ( ROM or EEPROM)
This IC holds flash or booting information(program). When this IC damage we can see software problems in your phone as follwoings.

Power on failure

Booting faults.( only booting screen)

Phone will stuck

Battery empty quickly

Some applications are not worked( camera ,Mp3,Video Bluetooth ...etc )

Phone work as a unconditional

VCO(Voltage Controll Oscillator)
VCO is the RF signal generator. It makes clock frequency which is used to run digital components. When this IC is damaged digital components fail to work and the result is power on failure.

Power on failure

Signal faults

SIM IC
This IC is used for controlling SIM card data. when it is damage you can see following faults. This is a crystal IC because of that when fallen down your phon like this IC will be damage easily. Therefore we can say following faults are common faults in nowadays.

Insert Sim

unablet to power on with sim card

Sim not accepted.

Key Pad IC
This IC is used for Controlling Key pad circuit.We can see this IC as crystal and normal type.because of that when fallen down your phon like this IC will be damage easily. Therefore we can say following faults are common faults in nowadays.

Key pad not work as a order

Key pad stuck

When power on one key is dialing continuously

When press a key phone will shut down or restart

Key pad work as a unconditional

LCD Light control IC
This IC is used for controlling keypad and LCD lights. We can see this IC as crystal and normal type. when this is damaged we can see following faults.

Key pad lights not work

LCD lights not work

White Display

Display not work

When you see like above damages dont try to do remove that ICs. Because there have a method for solving any faults in mobile phone. Therefore firstly try to understand about mobile phone ICs and about its works and also damages.

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