Tienda | Forums | Blogs | ES |

Samsung UN50FH5303 very high voltage on LED strips BN44-00668A board

This post was translated, if you want to see the original version click here

Good afternoon everyone and I hope you have a very happy year !!!

I got this samsung led tv to repair with several burned leds but notice that after replacing them the board delivers about 3.7 [/size[=15.6pxvoltios to each led and heats up the you throw and modified several source plates to reduce them [/size[=15.6pxvoltaje but with this plate I can't hit anyone who knows it or has the diagram me [/size[=15.6pxpodria

lend a hand? thank you very much!

1 Proposed Solution

Hi Leonardor, you can lower the voltage that feeds the LEDs as follows: 1) Enter the service (or user) menu. In the image screen give ok or enter 2) with the down arrow you are located in BACKLIGHT or Back Light or backlight and give ok or enter. 3) If you have scale from 0 to 20 with left arrow. you lower it to 12 or 15 (and you measure how the voltage drops) If it is in percentage it lowers it to 70, 60 or 50% depending on the voltage drop, then press ok or find out. Of course a little will lose contrast, but then you can place yourself in cont. and brightness and you regulate it at ease)
  • This can also be done on the source plate. You look for the negative line (- LED) and following the track you get to a mosfet, leg 3 of this is the one that goes to mass through an R or several in parallel. If it is only one, you must change it for one of somewhat greater resistance and try, if they are several, as they are in parallel you can take one or two resistors which increases the value of the total R. Other times the LED line - does not go to a mosfet but to an integrated one that has the built-in mosfet. In this case the leg of the integrated one that goes to ground has 1 or more r in // (vary said R)

  • 4 days ago

    Avatar de leonardor

    Indeed friend has a series of resistors in parallel and taking 4 of them I managed to lower the voltage I had it tested a few hours and the client already removed it I hope it lasts a lot thanks for the contribution and the help provided to comment so I value it!

  • Very good leonardor, it will be until next time. I tell you in case you do not know how this forum works that when solving the problem you must click on the proposed Solution of who else helped you to solve it. In this case as only my proposal is, a click on mine, this way this post is closed as solved and can be served by another colleague with the same problem. Thanks greetings.

  • if as you say you want to rate the click you must do it above in my first comment where it says: 1 (in red) and then proposed solution. regards