FLY EZZY Service Manual

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FLY EZZY

SERVICE MANUAL

CONTEANT LIST
Chapter 1: Summary
Chapter 2: Exploding Diagram
Chapter 3: Explanation of Schematic
Chapter 4: Failure Analysis
Chapter 5: Manual of tool software

Chapter 6: Tools List

Chapter 1: Summary

This streamline and comfortable handset is a perfect combination of humanized design and
Excellent craft. Besides the basic call function, FLY EZZY provides you with a colle
Functions including sweet ring tone, cartoon incoming-call animation, File manager
(T-Flash card supp

ort). It also supports MMS and increment service which facilitate your work and

entertainment.
In order to support technicians to be familiar with FLY EZZY handset, please master the method of servicing.

In addition, we provide corresponding technical data, including CKT base band, RF and software. There are

ction of practical

also many base band and RF test reference points and
examples. Hope it could give you some help.

Main specification and technique standards of FLY EZZY are as below:

Standby time:

Talking time:

Style of network

description of circuit. You can refer to maintaining

160-240 hours-

160-200min

GSM900, DCS180

Chapter 2: Exploding Diagram

The main board PCB

The main board placement

Chapter 3: Explanation of Schematic

AD6548

MTK6223A

MTK6223A

Picture 3.1 MT6223A principle picture

3.1 Principle of RF circuit

3.1.1 Principle of receiver circuit

3.1.1.1Rx signal flow chart:

Picture 3.1.1 Receive signal flow frame

3.1.1.2 Main function of RF

RF part generally means the analog RF and IF process system ,including Antenna system、

TX path、RX path、Analog modem and Frequency Synthesizer .

RF Circuit deals with the RX and TX of wireless signal, with responsibility for the bidirectio

Transmission of speech and data between the MS and BS through the air interface. In detail RX part

nal

Accomplishes the AGC amplifying, mix and demodulation of RF weak signal received from BS, The
Final signal output from RX part is the analog baseband I/Q signal. The final RX I/Q will be sent to
Baseband Circuit for later disposal. On the other hand TX part deals with the signal modulation,
Up-conversion mix and power amplifying of analog I/Q signal received from baseband, generating
Burst which meets the GSM specification. And then the bursts are transmitted to Base station through
The antenna. The signal interface between RF Circuit and Baseband is analog baseband I/Q signal. T
Perfo ile phone!

rmance of RF Circuit can directly affects the signal transmission quality of the mob

The schematic of RF block for MTK GSM Dual-band RF solution is show below:

he

From the chart we can see that the RF part is mainly composed of a highly integrated CMOS

Transceiver chip (AD6548), some RX Saw filters, reference crystal oscillator, power a
Antenna switch module, antenna a

3.1.2 Direct Convers

ion Receiver

nd the matching components between each other...

–Differential LNA

–Programmable Gai

–Th receive path

e

RX Channel Select Filters–Integrated Active

n Baseband Amplifiers

mplifier,

3.1.3 Translation Loop Direct VCO Modulator
–Integrated TX VCO and tank

–External TX filters eliminated
–Integrated Loop filter components
–Transmit Path

AD6548 uses only a single VCO source to derive the local oscillator signal for both the Feedback Down­Converting Mixer and the Quadraturemodulator

TX PA: SKY77542

RX Saw filter Circuit

TX PATH:

3.14 26MHz Clock:
–The entire system including V

loop filters are fully integrated.

The only external component is the frequency reference.

–

CO, tank, fractional N dividers, sigma delta compensation, charge pump and

26MHz Clock Reference circui

3.1.5 High performance multi ban
–Fast Fractional-N Synthesizer

d PLL system

Integrated Local Oscillator VCO

–
–Fully Integrated Loop fil

ters

–Crystal Reference Oscillator & Tuning System

.1.6 Po

3 wer Management

Integrated LDOsallow direct battery supply connection

–

3.1.7 Frequency ranges

The frequency ranges of the synthesizer for RX mode:
RX mode

E-GSM 900 925.2MHz ~ 959.8MHz
DCS 1800 1805.2 MHz ~ 1879.8MHz

The frequency

ranges of the synthesizer for TX mode

TX mode

EGSM900 880.2MHz ~ 914.8MHz

DCS1800 1710.2 MHz ~ 1784.8MHz

3.1.3 AD6548 Function Block Diagram

3.2Principle of base band circuit

3.2.1 Whole introduction of base band circuit

3.2.2 Explanation of power circuit and in-and-out circuit

Power source is provided by MTK MT6223A and periphery components, main function as below:
A.
B.
C.

D.
E.

2.8V-5.5V Input Range
Charger input up to 8V
Seven LDOs optimized for specific GSM Sub-systems

One LDO for RF transceiver

High operation efficiency and Low stand-by current
F. Li-Ion battery charge function
G. SIM Card interface
H. Two open-drain output switches to control the LED and vibrator
I. Three NMOS switches to control RGB LEDs
J. Thermal Overload Protection
K. Under Voltage Lock-out Protection
I. Over Voltage Protection
M. Power-on Reset and Start-up Timer

1

．7 channel power supply

23A 7 channe supply:

MT62

l power

LDO Power Function
VCORE .5V 1.8V/1 Digital core voltage LDO output
VDD 2.8V Digital I/O voltage LDO output
AVDD
VCTXO

2.8V

2.8V

Analog LDO output

Crystal or VCTCXO LDO output
VMEM tput 1.8V/2.8V External memory LDO ou
VSIM .3V 1.8V/3 LDO output to SIM card
VRF

2.8V

LDO for RF transceiver

2、power on/off circuit

After the handset power off, the pin PWRKEY is pulled high. The pull-up resistance is inside the

chip .When the power key is pressed, the pin PWRKEY is pull low, then the MT6223A turn on all the Power supply
function and the baseband chip enter working status. So the pin BBWAKEUP is pulled

key can be released; the CPU-baseband chip can control the MT6223A.

Charge Circuit

MT6223A charge management function:
1、Charger detection

high. At that time, the power

2、Battery voltage measurement
3、Charging current measurement

4、Over voltage Protection
5、Charge mode selection

MT6223A is available to control the pulsed charging current. The pin CHRIN is to detect the

Charger. The pins ISENCE/BATSENES can calculate the battery voltage by detect the voltage of R400, and calculate

the charge current by the voltage of the resistance R400. In different charge mode, Baseband chip sent the

different PWM pulse signal to MT6223A, so the MT6233Acan control

The charge process include three states: pre-charging mode, constant current mode and constant voltage
Mode. If the battery voltage is bellow 3.2V, the handset enter pre-charging mode; If the battery voltage

the process of charge.

is over 3.2V, it enter the constant current mode; If the battery voltage is higher than 4.2V, it enter the
constant voltage mode

.

3.2.3 SIM interface

SIM interface circuit

The power management chip supply the interface between the SIM card and baseband chip, the

Key signal is: SIM_CLK (the clock signal), SIM_RST (the reset signal), SIM_I/O (I/O signal),
VSIM (SIM power supply).

3.2.4 Principle of audio frequency circuit

The Audio Frequency (AF) circuit includes three parts: RECEIVER and SPEAKERs, HANDSET

MIC, ERAPHONE and HANDFREE MIC.

There are 4 speakers; each speaker is drove by an AF amplifier. The baseband chip sends the AF
Signal to the AF amplifier though MP3_OUT port. After the AF signal is amplified, it goes to the
Speaker. The RECIEVER is drove by the baseband chip directly. As an electrets tone arm, the MIC
Needs power support when working. The MICBIASP/N port of the baseband chip supports bias
Voltage for Mic. The EARPHONE port of the FLY EZZY is dual-used with the USB port. For more details
Please refer to “communication ports” in later part.

1、Receiver

2、Louder speaker

Figure 3.2.5 Circuit of receiver

Figure 3.2.6 Circuit of louder speaker

3、

Handset microphone Earphone

、Hands-free microphone

4

3.2.5 LCD circuit

igure 3.2.7 Circuit of MIC bias voltage circuit of mobile phone

F

Figure 3.2.8 Circuit of Hands-free microphone

Memo generation base band chip

ry and all the periphery equipments used the same bus based on the 1

st

That made the system structure to separate
The periphery equipm nd all of them use the 52M
System clock simu

LCD use series type LCD and four control bus (LPCEOB_MAIN_LCM is chip select signal;

very slow. Considering that, MTK have altered the hardware

ents (like LCD and NAND etc.) from memory bus a

ltaneously

Figure 3.2.9 LCD interface circuit

LPA0 is select
bus for register and commend; LWRB is LCD writes strobe; LRDB is LCD read strobe, LRSTB is re
LCD is controlled by baseband IC.

Display data is transferred to video RAM in LCD driver by I/O port in DMA mode. So system
Can response quickly and multimedia runs fluently without mosaic or picture feeling. Three
Common-anode LEDs in charge of background light supplying. Three voltage sensitive resisters are
Needed to protect the LCD from electrostatic harm and extend the life of LCD.

set signal.

3.2.8 T－Flash circuit

T-Flash card interface: VDD is supplied by MT6233A

3.2.10 FM

U600 is the FM chip to supply the function of FM radio.

3.2.11 key interface

When key is pressed down, the matrix KCOLX status is pulled down to low. Interrupt occur

Then Baseband can judge the key’s location, so system implements corresponding function.

s,

Chapter 4: Failure Analysis

The main fail cases:

Fail to download; Fail to power on; Fail to make a call (due to RX or TX); Fail to charge; RX/TX
power fail; Audio malfunction; No vibration; No display; Power supply fail; SIM check fail and so on.

In mobile circuit system, all the electrical connecting trace can be divided into three types, such
As power supply trace, controlling trace and signal trace. When analyzing the RF failure case, for the
Active circuit we should first check the power supply, then control circuit followed by the signal flow
Path to remove the failure step by step. When debugging the RF malfunction, we should diagnose the
RX part first before TX.

With the help of oscilloscope we can diagnose power supply issue, control signal trouble and
Some low frequency signals, such as I/Q signal, RTC signal, crystal oscillator signal and so on. We can
Measure the signal features such as amplitude, frequency, duty cycle etc. We can also use multimeter
to measure power supply DC voltage. For RF signal, we usually use spectrum analyzer to check signal
Spectrum and amplitude in frequency domain.

We provide a useful phone maintain software - META. Some introduction about META will be

Showed below.

4.1 Analysis of base band failures

4.1.1 The handset can not be power on

Interrelated components are mainly as below: PMIC 、Baseband chip (MT6223A),MCP Flash，RF

Transceiver (AD6548), 26MHZ VC TCXO, 32KHZ crystal. you can measure the 7-route LDO voltage: VCORE
（1.8V）、VDD（2.8V）、VADD（2.8V）、VCTCXO（2.8V）、VRTC（1.5V）、VMEM(2.8V). Then
measure if the 26MHZ,32KHZ output the CLK signal with right frequency to baseband, if no fault occurs,
continue to check FLASH, baseband chip by download a code, if can download DA, indicate baseband is
normal, otherwise re-soldering the baseband chip and memory .replace these chips if all the step can’t solve the
fault.

4.1.2 Display failure
FLY EZZY is a bar phone, LCM is soldering on the PCB directly. A bad soldering can lead to display

Failure, you can check it with your eyes or measure the PIN with digital multimeter, if the soldering is
OK, maybe it is the problem of LCM or MAINPCBA. You can change the LCM or repair the
MAIN PCBA.

4.1.4 Keys failure

ey circuit is simple, check the net is short or not. If the issue is still there, you need to check

K
The BB chip at last.

4.1.5 Voice cannot be sent or received

This often occurs in a mobile phone. You can enter into engineering mode by inputting *#060905#,
First you go to the test item “receiver”, and then you can hear “du du” sound if the receiver is good.
Otherwise you need to test its resistance with multimeter. It should be 32ohm. If the resistance is much
bigger it means the receiver is bad, so you can change for a good one. Second you go to the test
“echo” and test MIC. Huff at MIC then there w

k. Otherwise you must check the microphone bias circuit, test bias voltage and output signal,

o
Microphone resistance sho

4.1.6

No voice in speaker

uld be 2.2k OHM.

ill be an echo at receiver that shows the microphone is

item

First you can check if the audio source can output from baseband

chip with a headset. Then check

speaker resistances see if it’s 8ohm or not. If not, the speaker is bad. Otherwise you need to check audio
PA circuit. After repaired, you can test it on engineering mode again.

4.1.8 T-Flash card failure

T-Flash card circuit is very simple, so you must pay more attention to card socket to see if it is
Soldered well.

4.1.9 Cannot download software

There are many reasons that can lead to download failure, but the problem of the analog switch IC,
Which is used to control the dual-used port by headset and UART, is the most common? So you need to

Pay more attention to it.

4.2 Analysis of RF failure

RF failure often occurs in calibration or capability test, the best diagnostic method is to use
Wireless universal tester, spectrum analyzer and signal source matched with META tool to test it.

Corresponding components with the RF receiving mainly are: antenna switch saw filters,
matching circuit etc. You need to check if one of them is bad soldering or damaged. If power received
is too low maybe the RF circuit is cut off, you need to check saw filter, matching circuit, and antenna
Switch and control signal etc. If the bit error is too high, it may be because the saw filter is not
Qualified.

RF transmitting circuit associated components is mainly as below: base band MT6223A, RF
Transceiver AD6548, attenuator, RF PA, antenna switch etc, main test items including power value,
power vs. time, modulation and switch spectrum etc. The current consumption when transmitting RF
signal is about 200 mA. So if the current is too low, it means the PA doesn’t work properly, you need
to change it for a new one.

Chapter 5: Manual of tool
software

5.2 Flash Tool

1) Run “flash tool”, then you can see the window as below.

2) Click File, first click” Open Download Agent …”, choose“CUSTOM_AllInOne_DA’’ in a Pop-up window; then click
“Open Scatter—loading file…”，choose “scat”; At last, click “ROM”, Then you can select the software (usually saved as
a .bin file) which you want to download

3) Connect the software download cable to the USB port of computer.

4) Click” Options”, choose right“COM port” in use, then click” Format FAT…”choose” Auto Format FAT” in a pop-up
window. Other settings you can leave them as “software default

5) Download”. Then connect cable with handset and power on the phone. The progress bar will move and begin downloading.
You need to wait for a few minutes (picture as below)

6) Downloading succeeds when the below picture occurs.

When need to download software

· Upgrade software to higher version. Bugs of function and performance will appear during

Using the handset. To improve the function and performance of the handset, the
Manufacturer will improve the software and release new software version. Users can
download new version to improve the function and performance of the handset.

· Program errors or disorder because of improper setting by users, e.g. the handset can’t

power on, or being locked, and so on.

· In principle, it is not allowed to download a software lower than the current version, unless

It’s specified.

Caution: Before downloading software, please save all information and phone numbers in the

handset. After the software is downloaded, the handset will delete all the information and

restore to the factory default software environment.

5.3 CKT maintain software introduction －META

5.3.1 META－RF TOOL

Step 1. Open Maui META and select correct COM port ，META status window shows’ Please
reset target’ ,otherwise if it is in’ Connect with target’ status, please click ‘Reconnect’。

Step 2: Connect the download cable between the corresponding computer COM port and the target
MS. Then power on the mobile .At this time META will detect the mobile and order the mobile

into META mode. The META status window will then change to ‘Connect with target’.And then

You may select RF Tool from the pull down menu.

Just pop up the RF tool option group as below:

5.3.2 The features of META RF Tool PM

PM is used for measuring the receiver Rx level at a given RX channel:

Testing result of Power

At first you should configure the Universal wireless communication tester such as Agilent 8960 or
R&S CMU200 please follow the below picture for your configuration guide:

In META page PM, please click RX Path Loss Setting into AGC PATH LOSS setting page. Click

Upload from flash button to read the RX path loss parameter form the mobile. If you have not loaded
the correct database file yet, META will notice you to open a database. Please follow it and then you
will see the target RX path loss parameters for different channels in the AGC path loss window.
Please note that all the RX loss values should be in the tolerance range of ＋/－5dB, otherwise it
Should be a hardware failure.

Follow below settings and press ‘start’ button to active RX measurement. Due to the System

simulator (8960) downlink Cell power is －70dbm,The Ant power reported from the mobile should

be about －70dbm, tolerance+-5dB. Otherwise it means there is some defect with RX path. Please
Check the GSM RX SAW and the surrounding circuit, like ASM and RF test connector.
For DCS/PCS band, do the same operation except for the band select and the 8960 band settings.
Note that the ARFCN should be the same setting as the 8960 Broadcast chan.

RF Tool TX level and profile

TX level and profile is intended for checking the Transmitter’s output power, ramping profile

at a given channel and power control level.

TX level and profile TSC 为 5

Set the 8960 to non-signal mode

Set Expect burst TSC code of 8960 the same as META indicated.

CONFIDENTIAL

Set 8960 Traffic band for EGSM, Traffic Channel to 20,MS TX Level:5 and wait for receiving

the MS burst.

Press GMSK level and ramp setting button into GMSK APC profile setting page：

Follow below setting page the set the corresponding TX parameters：ARFCN, TSC, PCL DAC

etc. Then click Start button to start transmitting burst.

If the Target MS’ TX function is OK you may see a TX PVT profile from the 8960 as follows:

If you can not see anything or it shows fail in the 8960’s PVT window, please follow below debug
wizard to check and remove all the failure about TX path.

1. First of all we use oscilloscope to check PA TX enable control signal waveform：PA_EN, The normal case
shows below; Otherwise please check Baseband circuit.

2. PA Vapc control signal waveform ：VAPC （GSM LEV5）

Chapter 6: Tools List

5.1 Downloading Operation Manual

Reference: Flash_tool.exe

5.2 Write SN Operation Manual

Reference: Maui META ver. 6.0952.0

5.3 Calibration Operation Manual

Reference: Maui META ver. 6.0952.0