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    #41
    Re: I Don't Understand

    Originally posted by budm View Post
    I would run constant current of 120mA (80% of the max spec.).
    The VF of the LED will vary withe current flwoing through the LED, temperature all affect Vf, that is why you should use constant current source, 30V may be OK it depends on the Vdrops of the Constant current active control element at the needed current and variation of the total Vf of the LED string, you want it to have head room for the Output Voltage to go up and down as needed to maintain constant current.
    See page 12 of the graph which is typical spec provided by the LED manufacturer which I doubt if you have it for your LED. If you have constant current power supply then you do the measurement and see what you get with your LEDs you will be using.

    https://cdn.badcaps-static.com/pdfs/...7f6e02e49a.pdf

    Good caps: I.E. Panasonic FM/FC/FR series, and many other Japanese manufacturer.
    Unless I can somehow modify this circuit so that it puts out 120ma instead of more than double that amount which it does now ... I wont be using it at all ... unless I break that series up into two sets and run them in parallel...

    Comment


      #42
      Re: I Don't Understand

      Originally posted by EasyGoing1 View Post
      Unless I can somehow modify this circuit so that it puts out 120ma instead of more than double that amount which it does now ... I wont be using it at all ... unless I break that series up into two sets and run them in parallel...
      I have been watching this post to see if you have figured some way to make it work

      I have some LED power supply module that are the same exact way that you have to match the current level but when you try to do this the voltage goes up

      What I found out is that the LEDs that I was trying to use did not match current draw that the LEDs that were in the LED module light

      I have not yet figured out how to overcome this problem yet

      Right now now I do not have time to figure this out

      Maybe the week of Thanksgiving when I am off from work I will have some time to figure this out and some other project problems at this time
      Last edited by sam_sam_sam; 11-08-2018, 05:26 AM.
      9 PC LCD Monitor
      6 LCD Flat Screen TV
      30 Desk Top Switching Power Supply
      10 Battery Charger Switching Power Supply for Power Tool
      6 18v Lithium Battery Power Boards for Tool Battery Packs
      1 XBox 360 Switching Power Supply and M Board
      25 Servo Drives 220/460 3 Phase
      6 De-soldering Station Switching Power Supply 1 Power Supply
      1 Dell Mother Board
      15 Computer Power Supply
      1 HP Printer Supply & Control Board * lighting finished it *


      These two repairs where found with a ESR meter...> Temp at 50*F then at 90*F the ESR reading more than 10%

      1 Over Head Crane Current Sensing Board ( VFD Failure Five Years Later )
      2 Hem Saw Computer Stack Board

      All of these had CAPs POOF
      All of the mosfet that are taken out by bad caps

      Comment


        #43
        Re: I Don't Understand

        Originally posted by sam_sam_sam View Post
        I have been watching this post to see if you have figured some way to make it work
        I'm about as stubborn as they get ... I WILL get this working one way or another ... know that! I prefer using the method that is as stable and long term as possible, and the solution that people agree with - who know more than I do ... but if that avenue fails, I've got wire cutters and a pretty decent soldering iron ... bunch of caps and resistors and diodes laying around ... ill spit and duct tape something together eventually ... but for the time being, I sit among the great weevils on the mountain and digest as much knowledge as I can before they get sick of me ... ill let you know what the final solution is when I get there. :-)

        Comment


          #44
          Re: I Don't Understand

          Originally posted by EasyGoing1 View Post
          I'm about as stubborn as they get ... I WILL get this working one way or another ... know that!
          I have the same problem

          Originally posted by EasyGoing1 View Post
          M I prefer using the method that is as stable and long term as possible, and the solution that people agree with - who know more than I do ... but if that avenue fails,
          Yes I prefer to do it this way also

          Originally posted by EasyGoing1 View Post
          I've got wire cutters and a pretty decent soldering iron ... bunch of caps and resistors and diodes laying around ... ill spit and duct tape something together eventually ... but for the time being, I sit among the great weevils on the mountain and digest as much knowledge as I can before they get sick of me ... ill let you know what the final solution is when I get there. :-)
          But if all else fails resort to something like this
          9 PC LCD Monitor
          6 LCD Flat Screen TV
          30 Desk Top Switching Power Supply
          10 Battery Charger Switching Power Supply for Power Tool
          6 18v Lithium Battery Power Boards for Tool Battery Packs
          1 XBox 360 Switching Power Supply and M Board
          25 Servo Drives 220/460 3 Phase
          6 De-soldering Station Switching Power Supply 1 Power Supply
          1 Dell Mother Board
          15 Computer Power Supply
          1 HP Printer Supply & Control Board * lighting finished it *


          These two repairs where found with a ESR meter...> Temp at 50*F then at 90*F the ESR reading more than 10%

          1 Over Head Crane Current Sensing Board ( VFD Failure Five Years Later )
          2 Hem Saw Computer Stack Board

          All of these had CAPs POOF
          All of the mosfet that are taken out by bad caps

          Comment


            #45
            Re: I Don't Understand

            Originally posted by EasyGoing1 View Post
            Unless I can somehow modify this circuit so that it puts out 120ma instead of more than double that amount which it does now ... I wont be using it at all ... unless I break that series up into two sets and run them in parallel...
            Read post 34, I already show you how that 180mA comes about, so to change the LED current setting you just need to change the value of the resistor. It is all in the spec sheet.
            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


              #46
              Re: I Don't Understand

              BTW, if you remove one of the two R13 (2R20) resistor, the constant current will drop down in half to 90mA.
              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


                #47
                Re: I Don't Understand

                Originally posted by budm View Post
                BTW, if you remove one of the two R13 (2R20) resistor, the constant current will drop down in half to 90mA.
                NOPE!




                Attached Files
                Last edited by EasyGoing1; 11-08-2018, 08:22 PM.

                Comment


                  #48
                  Re: I Don't Understand

                  Where is the meter connected to? In series with the LED string? Unless that spec sheet diagram does not match what you have, or 5602 is no longer regulating the current.
                  See the calculation and how the 5602 is connected, verify if it matches your board lay out as far as R13 connection is concerned. I see that one end of the resistor is connected to pin 7, 8 for sure, most Chinese manufacturers will just copy the circuit from the IC manufacturer application circuits.
                  Attached Files
                  Last edited by budm; 11-08-2018, 10:47 PM.
                  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


                    #49
                    Re: I Don't Understand

                    [QUOTE=budm;861331]Where is the meter connected to? In series with the LED string?[quote]

                    Yes

                    Originally posted by budm View Post
                    Unless that spec sheet diagram does not match what you have, or 5602 is no longer regulating the current.
                    See the calculation and how the 5602 is connected, verify if it matches your board lay out as far as R13 connection is concerned. I see that one end of the resistor is connected to pin 7, 8 for sure, most Chinese manufacturers will just copy the circuit from the IC manufacturer application circuits.
                    OK, I'll have a look ... but im thinking if I just use two strings of LEDs connected in parallel it should be fine, unless it isn't bright enough but with 8 or 10 total of these LEDs I think it might be alright.

                    Comment


                      #50
                      Re: I Don't Understand

                      Originally posted by budm View Post
                      BTW, if you remove one of the two R13 (2R20) resistor, the constant current will drop down in half to 90mA.
                      So I fixed the lamp ... here's how I did it:

                      I ordered these CV/CC power supplies and I used these LEDs, and I made two serial strings of those LEDs and connected them in parallel... I got an old printer power supply that kicks out 30 volts but as it turns out all the LEDs needed was 16 volts ... and I set the current to 280ma and its working like a champ.

                      Comment

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