Voxtel W420 Repair Manual Download Page 1

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Voxtel

Repair Manual
Item: W420

Summary of Contents for W420

Page 1: ...Voxtel Repair Manual Item W420 ...

Page 2: ...cident endanger flying safety Don t use mobile phone in he building site avoid the contact bomb caused by radio signal Pay attention to the sign that forbid radio signal around before use mobile phone Don t use mobile phone near flammable gas or oil including fuel section under the board on the ship fuel or other transfer and deposited area For preventing the bomb caused by electromagnetic harmoni...

Page 3: ...W420 using RF accessory plug 2 2 Introduction of character and function Character Supporting trio band The mobile phone can automatic switch in GSM900 network DCS1800 network and PCS1900 network Choose best channel for calling The mobile phone can also automatic switch during the call without disturbing users And the ratio of connecting improves with the automatic switch Using trio method GSM900 D...

Page 4: ...tage 3 7V Battery voltage 3 7V Voltage Operation voltage 3 4 4 2V Operation voltage 3 4 4 2V Operation voltage 3 4 4 2V Transmit current Peak value 1 5A Antenna impedance 50Ω RF export power most 2W most 1W most 1W SIM Insert only Insert only Insert only Temperature Range 10 C to 55 C 10 C to 55 C 10 C to 55 C Table 3 1 basic technique parameter RF power export 33 dBm 2dBm 30 dBm 2dBm 30 dBm 2dBm ...

Page 5: ...XXXXX 3 6th common representative factory serial number second line handset model Form like V998 N5110 and so on The third line of form is group of numerical codes each access net symbol not to be all same The typeface on the true symbol usually printed by the needle printer the number is clear and the color is shallower It is can be seen that hits by needle if carefully look on it The imitate sym...

Page 6: ... just input PIN code easily The PIN code personal Identity Number is called individual identification code It is 4digit long established by user himself It belongs to the password of SIM card that protect security of SIM card Its original estate is not activating After its starting up GSM system will identify the mobile phone automatically after turn on the phone every time It will estimate validi...

Page 7: ...n Asian MoU investigating international roaming agreements The Phase II specification for GSM has now been defined merging GSM900 and DCS1800 documents number of new features are added to the system along with many minor adjustments The next step Phase II defines the addition of specific new services such as data and fax to GSM and DCS1800 5 2 GSM Network This is the GSM system The Mobile Stations...

Page 8: ...t a pair of channels one is uplink the other is downlink This pair of channels is called physical channel In GSM system the frequency interval is 200kHz The ARFCN of PGSM is 1 124 the center frequency of CH1 uplink is 890 2MHz When the value of ARFCN is equal to n center frequency uplink channel is fn f1 n 1 200kHz The center frequency of corresponding downlink channel need to add duplex frequency...

Page 9: ...re power The table above shows the maximum and minimum power levels on the mobiles in different systems The final row shows the power steps which are all numbered and how they relate to the max and min powers 8 Timing Control If the burst arrives at the correct time it will fit into its physical channel and not disturb any other burst that may follow it in the next timeslot However if it is delaye...

Page 10: ... base station SACCH When the MS is on a call it is constantly monitoring the Received Signal Quality a bit error rate measurement known as RxQual and the Received Signal Level a power measurement call RxLev These are constantly being sent back to the BS on a Slow Associated Control Channel SACCH FACCH The Fast Associated Control Channel is used to pass critical information to the mobile during a c...

Page 11: ...ent and received Once camped the mobile is ready to send or receive calls When a user dials a number and presses the send button on the mobile call origination takes place The mobile transmits a short RACH burst on the uplink using the same ARFCN as the BCH is using on the downlink The base station responds to the RACH by posting an AGCH Access Grant CHannel on the CCCH These are logical channels ...

Page 12: ...th midamble and timing information and send this to the mobile It then commends the mobile to switch base stations and then once the new call is established close down the old link and reallocate it to another user if necessary 6 Summary introduction of mostly chips used in W420 Chips used in W420 can be divided into flat and application manage according to function There is the introduction of th...

Page 13: ...with DBB control centre through ABB ABB controls system clock A D D A conversion background light of keyboard provide system power and charge interface etc There is the basic structure as follows Figure 6 2 ABB basic structure U602 Transceiver is a high integrated multi frequency low power cost transceiver there is the structure as follows ...

Page 14: ...n with power control function With its control part signal s amplify and signal s power control can be made by itself only It is divided to low frequency band EGSM900 and high frequency band DCS1800 PCS1900 Every part of the amplifier is combined with 3 sect amplifier Export power is controlled by a inter power control module which realize the control function through changing 3 sect amplifier s d...

Page 15: ...tructure Figure 7 1 shows basic control flow of W420 mobile phone It is shown in the picture that U201 is the core of control in the whole system It carries out all programs storage in U307 and control the whole system through U202 U304 and U302 According to the difference of function W420 can be divided as RF process circuit including receiver part and transmit part audio interface circuit Mic Re...

Page 16: ...ne side of this circuit connect to pin C12 of U202 which provide AFC AFC Automatic Frequency Control for 26MHz crystal the other side of this circuit pass through a more complicated path to provide system working clock a first input 48pin on U602 provide working clock for U602 b then processed in U602 pass through 47pin on U602 input Y9 on U200 provide 26MHz working clock for DBB c and then proces...

Page 17: ...BR1 KBR2 KBR3 KBR4 SW720 UP SW721 DOWN U309 V 1O 2 9 SW723 CAMERA 1 OMAP CPU VDDSH1 VDDSH3 2 U302 SDRAM 3 U307 M DOC U301 MEMARY 4 U402 CHARGE U303 V CORD 1 U200 OMAP730 VDDOMPE VDD Note This LDO encapsulation is very small it may weld unstable when jointing then lead system working abnormally Therefore make sure this LDO output normally first before adjusting hardware 7 4 RF process circuit recei...

Page 18: ...utput from mobile phone through probe After probe exiting switching close up signal output from antenna The max impedance of CN600 is 50 ohm max insert loss is 0 1dB FE600 is a RD switch controlled by DBB U200 its working band is GSM DCS and PCS structure as follows DDB U201 set voltage for V_TX_LOW and V_TX_HIGH which is two control unit of FE600 through external gate circuit Q600_A and Q601_A in...

Page 19: ...ecoding PCM decoding etc voice decode arithmetic manage Then the signals passes VSP port Voiceband serial port between U201 and U202 into U202 and managed by DAC in U202 Finally analogy signal are sent to earphone or headphone and transfer them into voice signal 7 5 RF manage circuit transmit circuit As the picture shows transmit circuit is made up of DBB U201 ABB U202 Transceiver U602 PA U603 RF ...

Page 20: ...20 RF signal after PA magnifying pass RF Switch Now RF Switch should be transmit elect connect estate to antenna then send out Mini USB connector Charging circuit SIM card interface circuit ...

Page 21: ...in mobile phone Only if the user s information in SIM card is legal could the mobile phone do networking finish user s operation and record other kinds of information U201 as interface circuit and management circuit provide working voltage clock reset spring for SIM card and connect its BSP to U201 achieve operation of input output user s information in SIM card SD card circuit As the picture show...

Page 22: ...here are two modes of SD card data transmission 1digit and 4digit This mobile phone use 1digit mode Headphone circuit of mobile phone Loudspeaker circuit of mobile phone Mike circuit of mobile phone Earphone circuit of mobile phone ...

Page 23: ...23 3 LDO circuit ...

Page 24: ...24 Cameramodule control circuit ...

Page 25: ...d to main board through CN702 The working voltages are 2 8V and 1 8V provided by 2 LDO as follows Data from cameramodule is paste up on LCD display indirect when Previewing Base band processor controls simple task only After taking photo it is need base band processor to move data from U201 to U302 for saving if user saves the photo Vibrator circuit control structure ...

Page 26: ...the resistances and capacitance around is them weld weakly or excursion and is there weld connective on PCB board 4 Connect an external power source set at 3 8V to pole of the battery seat If there is current passing the powermeter before ON it is illuminated that the mobile is creepaged Check voltage for power supply LDO when turn on the mobile the voltage value of U309 V IO 2 U301 V MEMORY U303 ...

Page 27: ...peaker reweld if it weakly 4 Measure the resistance of Speaker If the value is not 8ohm then displace the Speaker Speaker is damaged or its line is break off 8 7 The motor can not vibrate 1 Check the setting of the mobile if the vibrate is set at close then turn it on 2 Check weld for R751 R752 Q750 reweld if it weakly 3 Measure the voltage of Pin1 on Q750 when the vibrator working If its value is...

Page 28: ...ormal 2 Measure the voltage of VREG It may be mulfunction at Transceiver or the capacitance is damaged if the voltage value is not 2 8V 3 Measure the logic of TSPACT00 and TSPACT04 it may be mulfunction at DBB if the logic is abnormal Or else displace new RF Switch 3 PA part 1 Measure the input power of PA Please consult Transceiver if it is abnormal 2 Measure VBAT It may be mulfunction at ABB or ...

Page 29: ...17 Calculate battery coefficients Calculate battery coefficients 18 Charger OFF Flag Check Charger OFF Flag 19 Start Charger Start Charger 20 Charger ON Flag Charger ON Flag 21 Charge Current Test Charge Current 22 Stop Charge Stop Charge 23 Check SIM Card Check SIM Card 24 AFC Calibration 25 Initialize Test set Initialize Test set 26 Switch to GSM900 NSIG Mode Switch to GSM900 NSIG Mode 27 Switch...

Page 30: ...itch to GSM900 NSIG Mode 65 Init GSM AGC vs Channel Init GSM AGC vs Channel 66 GSM Rx Compensation at Ch1 67 GSM Rx Compensation at Ch20 68 GSM Rx Compensation at Ch40 69 GSM Rx Compensation at Ch62 70 GSM Rx Compensation at Ch80 71 GSM Rx Compensation at Ch100 72 GSM Rx Compensation at Ch124 73 GSM Rx Compensation at Ch975 74 GSM Rx Compensation at Ch1000 75 GSM Rx Compensation at Ch1017 76 Save ...

Page 31: ...M APC Calibration Initial GSM APC Calibration 116 Get GSM850 APC Power Get GSM850 APC Power 117 Calculate save GSM APC table Calculate save GSM APC table 118 Switch DCS NSIG Mode Switch DCS NSIG Mode 119 Initial DCS APC Calibration Initial DCS APC Calibration 120 Get DCS APC Power Get DCS APC Power 121 Calculate save DCS APC table Calculate save DCS APC table 122 Switch PCS NSIG Mode Switch PCS NS...

Page 32: ...at Ch531 166 PCS Tx Compensation at Ch568 167 PCS Tx Compensation at Ch605 168 PCS Tx Compensation at Ch660 169 PCS Tx Compensation at Ch712 PCS Tx Compensation 170 PCS Tx Compensation at Ch740 171 PCS Tx Compensation at Ch768 172 PCS Tx Compensation at Ch796 173 Save PCS Tx vs Chan Compensation Save PCS Tx vs Chan Compensation 174 Rx Check 175 Switch to GSM900 NSIG Mode Switch to GSM900 NSIG Mode...

Page 33: ... Mode 225 GSM Tx Check 128 5 Check GSM Tx Check 128 5 226 Tx Power 128 5 Check Tx Power 128 5 227 Time Mask 128 5 Check Time Mask 128 5 228 Peak Phase Error 128 5 Check Peak Phase Error 128 5 229 RMS Phase Error 128 5 Check RMS Phase Error 128 5 230 GSM Tx Check 128 19 GSM Tx Check 128 19 231 Tx Power 128 19 Check Tx Power 128 19 232 Time Mask 128 19 Check Time Mask 128 19 233 Peak Phase Error 128...

Page 34: ... 276 Time Mask 512 15 Check Time Mask 512 15 277 Peak Phase Error 512 15 Check Peak Phase Error 512 15 278 RMS Phase Error 512 15 Check RMS Phase Error 512 15 279 PCS Tx Check 810 0 PCS Tx Check 810 0 280 Tx Power 810 0 Check Tx Power 810 0 281 Time Mask 810 0 Check Time Mask 810 0 282 Peak Phase Error 810 0 Check Peak Phase Error 810 0 283 RMS Phase Error 810 0 Check RMS Phase Error 810 0 284 PCS...

Page 35: ...75 5 33 ORFS Offset 400Khz 975 5 34 ORFS Offset 400Khz 975 5 35 ORFS Offset 600Khz 975 5 36 ORFS Offset 800Khz 975 5 37 ORFS Offset 1200Khz 975 5 Check Switching spectrum 975 5 38 Start BER Measurement 975 106 Start BER Measurement 975 106 39 RBER ClassII 975 106 RBER ClassII 975 106 40 FER 975 106 FER 975 106 41 Rx Level 975 106 Rx Level 975 106 42 Rx Quality 975 106 Rx Quality 975 106 43 Change ...

Page 36: ...ment Change PCL 124 5 80 Start Tx Measurement 124 5 Start Tx Measurement 124 5 81 Average Power 124 5 Measurement Average Power 124 5 82 Peak Phs Error 124 5 Measurement Peak Phs Error 124 5 83 RMS Phs Error 124 5 Measurement RMS Phs Error 124 5 84 Frequency Error 124 5 Measurement Frequency Error 124 5 85 Time Mask 124 5 Measurement Time Mask 124 5 86 Switching spectrum 124 5 Switching spectrum 1...

Page 37: ...31 Change TCH 698 15 Change TCH 698 15 132 Start Tx Measurement 698 15 Start Tx Measurement 698 15 133 Average Power 698 15 Measurement Average Power 698 15 134 Peak Phs Error 698 15 Measurement Peak Phs Error 698 15 135 RMS Phs Error 698 15 Measurement RMS Phs Error 698 15 136 Frequency Error 698 15 Measurement Frequency Error 698 15 137 Time Mask 698 15 Measurement Time Mask 698 15 138 Change PC...

Page 38: ...evel 885 106 187 Rx Quality 885 106 Rx Quality 885 106 188 PCS measurement 189 Initialize System Initialize System 190 Run Mini Kernel Run Mini Kernel 191 Initialize GSM Test set Initialize GSM Test set 192 Switch RF Path to connector Switch RF Path to connector 193 Setup BCCH Setup BCCH 194 Setup TCH Setup TCH 195 Wait for MS Registering Wait for MS Registering 196 Ms call to BS Ms call to BS 197...

Page 39: ...660 0 243 ORFS Offset 400Khz 660 0 244 ORFS Offset 400Khz 660 0 245 ORFS Offset 400Khz 660 0 246 ORFS Offset 600Khz 660 0 247 ORFS Offset 800Khz 660 0 248 ORFS Offset 1200Khz 660 0 Check ORFS Offset at 660channel 249 Tx Max current PCS Tx Max current PCS 250 Start BER Measurement 660 106 Start BER Measurement 660 106 251 RBER ClassII 660 106 RBER ClassII 660 106 252 FER 660 106 FER 660 106 253 Rx ...

Page 40: ... GSM900 NSIG Mode Switch to GSM900 NSIG Mode 8 Switch RF Path to connector Switch RF Path to connector 9 Config to BCH TCH Mode Config to BCH TCH Mode 10 GSM Tx Check 40 5 GSM Tx Check 40 5 11 Tx Power 40 5 Check Tx Power 40 5 12 Time Mask 40 5 Check Time Mask 40 5 13 Peak Phase Error 40 5 Check Peak Phase Error 40 5 14 Switch to DCS NSIG Mode Switch to DCS NSIG Mode 15 DCS Tx Check 700 0 DCS Tx C...

Page 41: ...3 dBm 0 12 Indication of RX_LEV at 100 dBm 104 dB 96 dB Indication of RX_LEV at 45 dBm 49 dB 41 dB Quality of RX_LEV RX_QUAL No more than 2 Table 10 1 GSM frequency band test parameter 2 DCS frequency band The number of Low band channel is 512 transmit frequency of low band channel is 1710 2MHz receive frequency is 1805 2MHz The number of Intermediate band channel is 700 transmit frequency of inte...

Page 42: ...eive bit error test of RES II at 102 dBm 2 Receive frame erasure rate of RES II at 102 dBm 0 12 Indication of RX_LEV at 100 dBm 104 dB 96 dB Indication of RX_LEV at 45 dBm 49 dB 41 dB Quality of RX_LEV RX_QUAL No more than 2 Table 10 2 PCS frequency band test parameter 10 2 analyse equipment and maintain tool in common use CMU200 HP8960 CMD55 signal generator HP8594E Spectrum analyzer HP854810 HP5...

Page 43: ...contain LCD display function but also contain backlight control function Speaker Receiver and Motor even Sensor and any other interface commonly It is an important composing module in mobile phone MCC Mobile Country Code 3digit stand for country code that user in MCU Micro Controller Unit MNC Mobile Network Code 2digit stand for network code user in MSIN Mobile Subscriber Identification Number Use...

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