LED TV dummy load.

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  • capwizard
    Badcaps Legend
    • Jun 2016
    • 1991
    • USA

    #1

    LED TV dummy load.

    Any help will be appreciated. I try to built "universal TV LED screen dummy load." .

    Basically, put a lots of LEDs try to cheat LED driver to work. So we can distinguish the problem is at LED screen or LED driver.
    Last edited by capwizard; 12-06-2016, 01:41 PM.
  • ReeceyBurger123
    Never Give Up !
    • May 2014
    • 7325
    • Britain

    #2
    Re: LED TV dummy load.

    Just use some 10w leds in series to match the output load of the driver easy
    Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

    https://www.facebook.com/Telford-Tel...7894576335359/

    Comment

    • capwizard
      Badcaps Legend
      • Jun 2016
      • 1991
      • USA

      #3
      Re: LED TV dummy load.

      Maybe some 10w leds and some 3v leds, but for some critical driver we will need exactly same current.

      TV LED screen dummy load version I : This is work OK, but customer will think you still in school.
      TV LED screen dummy load version Il : add some protection.

      TV LED screen dummy load version Il: 10 x10 =100 leds, some TV have 8 strips, I need 8 of them.

      TV LED screen dummy load version Iv: use Edge tv strips but is hard to solder

      Best way to do it probably have customer made PCB . (last two pic)
      Attached Files

      Comment

      • ReeceyBurger123
        Never Give Up !
        • May 2014
        • 7325
        • Britain

        #4
        Re: LED TV dummy load.

        Awesome
        Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

        https://www.facebook.com/Telford-Tel...7894576335359/

        Comment

        • capwizard
          Badcaps Legend
          • Jun 2016
          • 1991
          • USA

          #5
          Re: LED TV dummy load.

          Maybe modified form this. cheap. Pic 1

          https://www.aliexpress.com/item/SMD-...999.414.kjp8Qb
          Attached Files

          Comment

          • capwizard
            Badcaps Legend
            • Jun 2016
            • 1991
            • USA

            #6
            Re: LED TV dummy load.

            Instead of LEDs, can I use this:

            http://www.eevblog.com/forum/project...-load-project/
            http://www.eevblog.com/forum/project..._next=prev#new

            Comment

            • capwizard
              Badcaps Legend
              • Jun 2016
              • 1991
              • USA

              #7
              Re: LED TV dummy load.

              Must-have Sharp LG Vizio edge led tv dummy load.

              I need to make 100% sure Sharp LC60LE660U TV problem is caused by edge LEDs .
              The easy way is to use the same one as a tester.

              What happened to test different size TV, I will need universal LED dummy load!

              Sharp LC-52C6400U LC-52LE640U LC-60C6400U LC-60LE640U LC-70C6400U LC-70LE640U LC-80LE633U

              at picture 2: the tester got hot in second will needs heat-sink like pic 3 (too long to carry around.)

              Pic 4,5 : Connector pin out
              Attached Files
              Last edited by capwizard; 12-13-2016, 09:50 AM.

              Comment

              • budm
                Badcaps Legend
                • Feb 2010
                • 40746
                • USA

                #8
                Re: LED TV dummy load.

                The key is trying to figure out how many LEDs there are in the string without taking the panel apart to get to the LEDs.
                Also need to find out if the LED strips are connected in series to form one big string or each strip is driven by its own driver.
                You can tell by looking at the PWM Controlled MOSFETs for the Cathode return for the LED string, if it has two PWM controlled MOSFETs then two drivers circuits are used.

                https://www.badcaps.net/forum/attach...5&d=1481642097
                I can see that it has four drive circuits for the LEDs' strings.
                Last edited by budm; 12-13-2016, 11:19 AM.
                Never stop learning
                Basic LCD TV and Monitor troubleshooting guides.
                http://www.badcaps.net/forum/showthr...956#post305956

                Voltage Regulator (LDO) testing:
                http://www.badcaps.net/forum/showthr...999#post300999

                Inverter testing using old CFL:
                http://www.badcaps.net/forum/showthr...er+testing+cfl

                Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                http://s807.photobucket.com/user/budm/library/

                TV Factory reset codes listing:
                http://www.badcaps.net/forum/showthread.php?t=24809

                Comment

                • capwizard
                  Badcaps Legend
                  • Jun 2016
                  • 1991
                  • USA

                  #9
                  Re: LED TV dummy load.

                  Thanks for your reply.

                  Over this Sharp tv has 4 drivers 34 LEDs each.

                  Can I use something else instead of LEDs to test ?
                  Last edited by capwizard; 12-13-2016, 11:26 AM.

                  Comment

                  • ZXCVBS
                    New Member
                    • Jun 2019
                    • 2
                    • Argentina

                    #10
                    Re: LED TV dummy load.

                    Sorry to revive an old thread, but I just wanted to ask.

                    I know i can calculate led resistance knowing the loaded voltage, and current.
                    i.e if i the power board outputs 200v 250 mA to the leds
                    I could use ohms law:
                    R= V/I 800 ohms. W = i*i*v 12.5W. An replace leds with a 800 ohm 12.5 W resistor
                    But if i lower those 200v (250 mA) to 20 v 2.5 A
                    can i connect that output to an electronic load, and start at minimal values until the led backlight is on its working condition range?
                    Don't know if i'm shooting a mosquito with a shotgun.
                    Last edited by ZXCVBS; 06-19-2019, 04:18 AM.

                    Comment

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