LED Panel information

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  • angelos
    Badcaps Veteran
    • Dec 2012
    • 562
    • South Africa

    #1

    LED Panel information

    Hi guys,
    I have a Samsung TV with a no picture issue. MY DC to DC IC (CM501) does not start up. I have read up on the web and I need to get this TV's panels schematic diagram. In other words the scalar board attached to the tv. This is the thin long board of which the COF IOC's are attached to. I have googled to no avail. It must be a secret. Is there a website that has Chimei Innolux circuit diagrams? I am so desperate.

    I was on a website and read how a technician fixed one of the panels using a schematic. He said that once the tv has stated up and the panel voltage 12V is p[resent then this voltage appears on the CM501 chip on pin 16 and 17. In turn this IC has to output a voltage apparently 3.3V back to the microprocessor. In turn the uP will send back a signal to the CM501, an enable voltage which will switch on the Vgh Vgl etc... As you can read this whole thing is quite involved.
    That's why i am asking for if anyone knows where i can get schematics of panels. Its like chicken teeth.
    Much appreciated.
    Angelos
  • angelos
    Badcaps Veteran
    • Dec 2012
    • 562
    • South Africa

    #2
    Re: LED Panel information

    Looks like i am asking a very difficult question. Is there anybody that has a schematic that uses the CMO501 chip?

    Comment

    • angelos
      Badcaps Veteran
      • Dec 2012
      • 562
      • South Africa

      #3
      Re: LED Panel information

      Sorry CM501

      Comment

      • arizanotlari
        Senior Member
        • Nov 2014
        • 158
        • Turkiye

        #4
        Re: LED Panel information

        ask to google

        https://cdn.badcaps-static.com/pdfs/...30c27440ae.pdf

        https://cdn.badcaps-static.com/pdfs/...bce05e021f.pdf
        https://www.badcaps.net

        Comment

        • angelos
          Badcaps Veteran
          • Dec 2012
          • 562
          • South Africa

          #5
          Re: LED Panel information

          Thank you very much Arizanotlari this is exactly what i need to find the problem.

          A blogger wrote,
          nvestigations done: Voltages from Power Supply Board were ok. The Voltage at the Scaler Board was checked. Input of 12V was reaching. But the VGL, VGH, AVDD, VDD and VCOM were missing. The voltage to Control IC CM501 at pin 16 and 17 was ok. But this IC was not producing the VDD of 3.3V, which should go to the uController IC to get back the enable voltage to its pin 9. So, this was not functioning. The VGL and VGH tracks were checked offline for any direct short. While the VGH was ok, VGL showed a 97 Ohms short to ground. In order to isolate the section, VGL track that goes to panel was cut. It showed same short.

          Which pin is the Vdd he spoke of, is it LX2 on the CM501? Is it perhaps Pin 11?

          Comment

          • Rajnhl
            Senior Member
            • Oct 2018
            • 94
            • India

            #6
            Re: LED Panel information

            VGL is negative voltage. check with red probe to ground and black probe to VGL point.
            if VDD 3.3v is missing then check for short on VDD line or ic may be defective. disconnect VDD from ic and give external 3.3v, see if panel works.
            5v to 15v input and 1.2 ,1.8v, 2.5v, 3.3v, 5v output module (selectable) is available.

            Comment

            • angelos
              Badcaps Veteran
              • Dec 2012
              • 562
              • South Africa

              #7
              Re: LED Panel information

              I will try again and see if i can find the problem. Have a look at the attachment. Is it pin 11 that should be measured?
              Attached Files

              Comment

              • angelos
                Badcaps Veteran
                • Dec 2012
                • 562
                • South Africa

                #8
                Re: LED Panel information

                Thank you Arizanotlari and Rajnhl for your replies. I solved my problem. The IC CM501 was faulty but when i soldered the new one into place i did not do a proper solder job. Its the first time that i soldered such a chip. I resoldered it and now everything is fine. The original chip was not outputting any voltages.

                Comment

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