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XOCECO LC-27FB26 Service Manual

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LCD TELEVISION
LC-27FB26

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Summary of Contents for XOCECO LC-27FB26

  • Page 1 LCD TELEVISION LC-27FB26...

  • Page 2: Table Of Contents

    CONTENTS Safety precautions………………………………………………………………………..… Alignment instructions …………………………….…….………………………………… Method of software upgrading……………….…….……………………………………….……. Working principle analysis of the unit……………………………….………….…………. Block diagram…………………………………..………………………………….………… IC block diagram………………………………………………………………………..…… Wiring diagram ……………………………………………………………………………. Identification criteria for the bright spot and dark spot of the LCD screen………….. Troubleshooting guide ………………………………………………………………..…… Schematic diagram…………………………………………………………………………...

  • Page 3: Safety Precautions

    Attention: This service manual is only for service personnel to take reference with. Before servicing please read the following points carefully. Safety precautions 1. Instructions Be sure to switch off the power supply before replacing or welding any components inserting/plugging in connection wire Anti static measures to be taken (throughout the entire production process!): a) Do not touch here and there by hand at will;...
  • Page 4 would be unable to work and no way to get it repaired. 2.11 Special care must be taken in transporting or handling it. Exquisite shock vibration may lead to breakage of screen glass or damage to driving circuit. Therefore it must be packed in a strong case before the transportation or handling.

  • Page 5: Alignment Instructions

    Alignment instructions 1. Test equipment PM5515 (video signal generator) VG-849 (YUV, VGA, HDMI signal generator) CA210 (white balancer) 2. The alignment flow chart (see below figure) Check DDC and FLASH To produce digital board and analog board All testing Adjust white balance Connect with central signal source, then check each function of TV such as station missing, analog control etc., check the output of headphone and speaker Input AV/SVIDEO signal, then check each function of all the terminals...
  • Page 6 to access. Press “CH+” and “CH-“ to move cursor up and down, when the cursor stays on a certain adjustment item, press “VOL-“ and “VOL+” to adjust. Press “MENU” exit to the level one factory menu; press “EXIT” to exit from the factory menu at any situation. Note: channel switch isn’t available at adjustment menu, only after return to level one factory menu, you can switch channel.
  • Page 7 31.469 59.94 HDTV 480p 44.955 59.94 HDTV 720p 33.716 59.94 HDTV 1080i 4.4 VGA terminal Input VGA signal (VG-849 signal generator), separate input VGA format signal of table 2 and check if the picture and sound are normal. If the image is deflection of the H-field, select manual correction of Advanced Video Menu.
  • Page 8 Digital Audio Output: AC-3, MTS: Mono 5) Setup menu, Tuning Band: Air 6) Feature menu, Sleep Timer: Off, Menu Language: English Note: Except for Color Temperature of Cool, the Advanced Video Menu of YPBPR/YCBCR and VGA channels sets according to the adjustment of factory. Trouble shooting Before servicing please check to find the possible causes of the troubles according to the table below.
  • Page 9 Symptoms Possible cause Screen position or size is not Check is the screen position and size is correctly set up. proper Picture is twisted and deformed Check to see if the picture-frame ratio is properly set up. Picture color changed or colorless Check the “Component”...

  • Page 10: Method Of Software Upgrading

    Method of software upgrading 1. Connect RS-232 cable to computer and TV set. The cable must be a female to female RS-232 cable, and the line is TXD to RXD and RXD to TXD cross-link. It’s popular for PC to PC connection.
  • Page 11 3. Copy the update tools (iDev.exe) to the path you want to do it, and double click it. 4. Select “setup” menu. 5. Confirm the Serial port is right. Base on the port which using for update. And set the band rate to 115200 (default).
  • Page 12 6. Select the “Image path” menu. 7. Confirm it’s the right file. 8. If it’s not right(Maybe you didn’t select it before),click the “…”button to select “*.ecc” file. Sometimes the image file you got it will be “*.rar ”or “*.zip” zip file, needs unzip it first.
  • Page 13 9. You also can click the setup button to select and config, but please don’t select the red one(update boot sector). 10. Then click the “down” button.
  • Page 14 11. You can see the “waiting” window. 12. Then power (off then) on the TV set. 13. After download, it will be burning.
  • Page 15 14. Last it will be finished 15. Press the (IR/ locate keypad) power key and holding for several second to force power off TV set, then power on again. It would be ok now. If it’s failure you can try once again.

  • Page 16: Working Principle Analysis Of The Unit

    Working principle analysis of the unit 1. NTSC signal flow: Antenna reception NTSC signal send to the integrative tuner FQD1236, which contains HF and IF amplifier circuit and video decoding circuit. It is controlled by main IC ZR39660 (inside CPU) through I2C bus.

  • Page 17: Block Diagram

    FLASH YPBPR2 SN3257C YPBPR1 LVDS JEPICO j-L003 ZR39660 Digital IF TUNER CAS220CS FQD1236 MK5 BGA400 AV_OUT Analog SIF SN3253C IIS IN CVBS1 HEF4052BT CVBS2 CVBS,Y/C IIS OUT D/A CS4344 Loudspeaker R2S15102NP AV1 AUDIO R2S15900SP Earphone NJW1109 AV2 AUDIO LC-27FB26 V1.0...

  • Page 18: Ic Block Diagram

    IC block diagram 1. ZR39140...
  • Page 19 Pin descriptions of ZR39660: (1) Serial Transport Input Port T4: MPEG Transport Port Input Clock T3: MPEG Transport Input Data U3: MPEG Transport Input Frame Y1: MPEG Transport Input Valid (2) HDMI Input D1,E3,F3,E2,F2,E1: HDMI Differential Data Pairs D2,C1: HDMI Differential Clock Pair C3: HDMI Serial Clock B2: HDMI Serial Data A1: HDMI Hot Plug Detect...
  • Page 20 (7) UART and I2C Interface N1: UART 0 Transmit P1: UART 0 Receive R1:I2C Compatible Clock 0 P2:I2C Compatible Data 0 M3:I2C Compatible Clock 1 M2:I2C Compatible Data 1 (8) Miscellaneous M4, N3: Two pins required to support the 24.576 MHz crystal N5: Power On Reset L4: Infrared Receive 2.
  • Page 21 Pin configuration of j-L003: (1) TTL SIGNAL INPUT 71: VS INPUT 72: HS INPUT 73: DE 76: CLK INPUT； 74, 78, 79, 80, 81, 82, 84, 93: RED Signal INPUT； 94, 95, 96, 97, 98, 99, 101, 102: GREEN Signal INPUT； 103, 104, 106, 107, 108, 109, 110, 111: BLUE Signal INPUT；...
  • Page 22 Pin descriptions of CAS220/CS: 61: RESET_N 79, 80 oscillator 13 Select I2C address 16: I2C data for host communication with the tuner 18: I2C clock to the tuner 19: I2C clock from host 20: I2C data from/to host 93,94: Differential input for IF 96,97: Differential input for SIF 63: Digital Sound Word select (L/R select) 65: Digital Sound Serial data output...
  • Page 23 4. MST9883 MST9883 is a Triple Video A/D Converter with Clamps & Pixel Clock Synthesizer. The triple ADC support 12 - 110 MHz Sampling Rate. It integrated 5-bit pixel clock phase adjustment for precise sample timing control. It’s Output support 4:2:2 Format Mode and it can Pin Compatible with AD9883A.
  • Page 24 Pin configuration of MST9883: Pin descriptions of MST9883: 54: Red analog input 48: Green analog input 43: Blue analog input 49: Sync on Green analog input 38: External Clamp Input 30: Horizontal SYNC Input 31: Vertical SYNC Input 29: Hold PLL Frequency, do not track HSYNC 56: Serial Interface clock 57: Serial Interface data pin 55: Serial interface address pin...
  • Page 25 39,42,45,46,51,52,59,62: Analog Power 26,27,34,35: PLL Power 11,22, 23, 69,78,79: Digital Output Power 1,10,20,21,24,25,28,32,36,40,41,44,47,50,53,60,61,63,68,80:Ground 5. R2S15900SP R2S15900SP is an audio signal processor. It has MUTE and Volume/Tone control. It can support 5 input selector. Pin descriptions of R2S15900SP: 2,27: AV1 AUDIO INPUT L/R 3,26: AV2 AUDIO INPUT L/R 4,25: DTV AUDIO INPUT L/R 5,24: EAR PHONE L/R...
  • Page 26 6. R2S15102NP 10Wx2ch(SE)/20Wx1ch(BTL) Digital Audio Power Amplifier R2S15102NP is a Digital Power Amplifier IC developed for TV R2S15102NP can realize maximum Power 10Wx2ch (VD=24V, THD=10%, SE) at 8Ω load. It is possible to replace from the conventional analog amplifier system to the digital amplifier system easily.
  • Page 27 SE operation Analog input #2(as same as IN1) BTL operation When this is connected to DVDD pin via the resister, Reversed signal of OUT1 is output to OUT2. PWM2 PWM input pin #2 (for phase compensation) MUTEL Mute control pin. When this is “L”, it becomes mute status. Power supply pin for power output stage #2 OUT2 Power Output pin #2...

  • Page 29: Identification Criteria For The Bright Spot And Dark Spot Of The Lcd Screen

    Identification criteria for the bright spot and dark spot of the LCD screen Quantity allowed Distance between two spots Category Criteria 15" 20" 22" 30" 40" 15" 20" 22" 30" 40" One single ≤5 ≤2 ≤5 ≤2 ≤3 spot Bright ≥15mm spot neighboring...

  • Page 30: Troubleshooting Guide

    Troubleshooting guide Begin Check power board , button board and power A red indicator cord lights? Yes, turn the unit on Check if the pin1 of X602 in data processing A blue indicator board is high level(+5V)? check V660/V661. lights? Check if the crystal in data processing board Display picture? starts, DDR clock is correct?
  • Page 31 (2) no picture, no sound No picture, no sound Check the color of indicator light Blue Check power Check the output voltage of board sockets X601~X604/X606/X608 No sound No picture Power board problem Refer to (3) checking Refer to (4) checking procedure procedure (3) with picture but no sound...
  • Page 32 (4) with sound but no picture With sound but no picture Display OSD MENU? Display LOGO? If pin5 of X602 (IRR) has signal? Check if the crystal in data processing board starts, If there is no picture DDR clock and DDR SDRAM are normal? in all channels? Check N108 and Refer to (6), (7), (8), (9), (10),...
  • Page 33 (5) Check image processing board Check the power supply of N803 Check if pin20, 21, 27, Check if the power supply of 30 of X801is high level L801/L802 are normal Check if pin3, 5, 26 of N806 Check the peripheral and power supply of output H/V-SYNC and clock N801, N802, DDR of data board Check the peripheral and power...
  • Page 34 (6) AV no picture Check if C136 and C137 input signals? Check if pin13 of N104 Check N105/N106 and the circuit outputs signals? from AV terminal to N104 Check the periphery circuit Check N104 and its from XC02 to N801 periphery circuit (7) S-terminal no picture Check if C105 and C138...
  • Page 35 (8) NTSC channel no picture Check if pin11 of TUNER226 output signals? Check if pin13 of N104 Check TUNER226 power supply outputs signals? and the peripheral circuit. Check the periphery circuit Check N104 from XC02 to N801 periphery circuit (9) ATSC channel no picture Check if pin6/7 of TUNER226 output signals? Check if the crystal of...
  • Page 36 (10) YprPb or Ycrcb channel no picture Check if pin4/7/9 of NB07 output signals? Check if pin64/66/67 of Check if pin4/7/9 of NB08 output NA51 are normal? signals? Check resistor Check NA51 Check NB01/NB02 Check NB07 rows RA63~ peripheral and the circuit from peripheral RA68 circuit.
  • Page 37 (12) HDMI channel no picture Check DETECT NA04 and its peripheral circuit? Check signals Check the connection to HDMI RA18~RA25 are normal? socket, NA04 peripheral circuit Check N801 and its peripheral circuit Note: N801 embeds FLASH, which stores DDC and HDCP information of HDMI, so make sure the connection between HDMI socket/interface and the bus line is well- going, the picture will display.
  • Page 38 b. No DC voltage output No DC voltage output voltage Check if DC of C536 is Check N502 or peripheral 3.3V(5V) circuit voltage Check main board Check if DC of V505 B is 24V voltage Check if DC of C537 is Check D515 or T501 Check FU502...

  • Page 50: Appendix: Exploded View

    APPENDIX: Exploded view (LC-27X26)
  • Page 51 PART LIST OF EXPLODED VIEW (LC-27X26) NO. PART NO. DESCRIPTION 780-X26W0-4F0 Front cabinet Screen 870-10391-00 LCD screen frame (top) 870-10393-00 LCD screen frame upright1 870-10395-00 LCD screen connection bracket1 863-60189U000 Power board frame 863-60188U000 Main board frame Power board assy CPU board assy 10 870-10397-00 Wall mount connection piece...
  • Page 52 603-L27FB26-12 Ver.1.0...

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