Porque Fallan los LEDS de un TV Causas y Reparación Duradera

Hello, welcome to a new video first for those who do not know about this topic I will make a brief description of thecomponents and operation of the LED lighting panel of a TV that will help them to know if your TV has a fault in this circuit we will see the lifetime of a TV of this type and from a ledindividual form we will also see the main cause of the faults in these LEDs and for people who are dedicated to the repair of these equipment themI will tell you how these are substituted with very good results so that the repairbe efficient and durable we start these are the LEDS here you can appreciate they arediscovered are these components come covered with these micas that areits light diffusers all come covered with this type of micas come mounted on fiber strips or rulers and they have a printed circuit with copper tracks by which the voltage of thefeeding here is your connector at one end these tracks are usually covered with white paint how canappreciate here the assembly on these strips facilitates a uniform distributionof the light but also its function is to dissipate the heat generated by the LEDS we'll see that in the back some bring a sheet of copper, othersthey can be aluminum and some do not bring it like this but you can appreciatehere the heating signals These are well fixed to the chassis of theTV which is responsible for dissipating the greatestamount of this heat generated here you can appreciate how they arefixed to the TV chassis this is the cardprincipal which feeds these LEDs, is the one that generates the voltage these are connected in series resembling so that they understand me to aseries of Christmas lights it can be a single circuit that feeds everything or canbe divided into several circuits for example this strip can bepowered with voltage independent of the others when it's a single circuit if an LED blows, it can causethat all this may mean that the TV is still listening to the audio but the image is not visible but it may also be that you do not turn on your TV because in some a protection circuit is activated if they are circuitsindependent in each strip if an LED is blown, only that strip will go out and it can cause the TV to see only half the image sometimesOne or more LEDs can be turned off And the others will remain on And in this onecase small shadows will be seen in one or several places on the screen and in the case ofthat the micas fall that also usually happens, that with the use and heat generated take off and fall into the television in those casesyou will see brighter spots on your screen since these are diffusersof light When the light intensity of each LED falls, it is very and you would notice a very bright or several ponto on your screen I was researching about the life time of an LED of these characteristics and it is according to the data of that information source approximately 100 thousand hours of useful life and of a TV in general with thisType of lighting between 60, 000 and 100, 000 hours of useful life in the description of the video I will leave the link of this information if we calculate in years the minimum life time of a television which is according to60 thousand hours would be approximately between 6 almost 7 years here the question is why many televisions fail in their LEDS very soon some just pastYour warranty time there can be several causesthe poor quality of the components failures in the power supply circuitvoltage or factory defects but the main cause is theabout heating the manufacturers specify that thecalculation of hours of useful life is working under normal conditions if we know that overheating affects lifespan and the LED strips are well made This is where the errors in the design oftelevisions that may well be mistakes or it may also have to do with theplanned obsolescence or planned obsolescence that is another issue to us what we repair the televisions should not interest us what we have to do, is to make this repair in an effective and lasting way I mention this because On several occasions these LED strips have been detected in some sections they are not properly fixed to the chassis or do not come with all the screws so that these strips are designed to be secured in the chassis or there are gaps and crevices in thechassis that make some parts do not arrive or do not adhere firmly tothe foil and that makes over heat some sections of these strips I have already detected in some models repetitively damaged LEDs on the same section for example in this, right now we will make a closer take in this model brings screws in most but in this section it does not bring screws to ensure clear that with the heating the strips gobending and stop making contact and the LEDs more prone tofail are those that are precisely the area where it is separated from the chassis well here we can see a shot more closely I tell them that I will describe thedetected errors and the way they were solved without showing the whole processrepair to not lengthen the video well before I'll tell you that the brand ofTV is Digitrex It is a generic television and can come with several brands in this case, as I mentioned, it is Digitrex brand and the complete data will appear on your screen this is the TV card to locate it, in casetouch fix this model and have different brand well here we see that the LED strip comes designed with four holes so that it can be fixed wellto the television chassis but the television manufacturer alonehe used three of them and in these it does not even have the perforation to be able to place a screw as I was telling you with the heat it doublesthe LED strip and stop seating well in the chassis, hereit can be appreciated this causes the LEDS in this locationwork with over heating and it is NOT working under normal conditionslike the rest this obviously affects your life time causing them to be damaged before others good the solution is if we are going to replace the LED strip make the corresponding perforations in the holes that have the stripsso they can fix them well to the chassis If they can replace the LEDindividually so forward but to avoid that the overheating persists in these areas we must fix it well and we will also use a method alreadyused in electronic components which is the heat dissipating fatwhich is a creamy fat already many know it is used incomponents of this type so that the component adheres wellto the dissipator, which in this case is aluminum even removing the screwAfter a while to replace the piece it is difficult to remove it because it adhereswith enough force We will use it on the spare strip or after having replaced the damaged LED we will apply it in the partlater if you want only behind each LED to save a little this cream and then proceed to fix it inits place also do the same with the other two although they are not damaged but this will help prevent the same thing from happening again we have another example this is a 40 inch samsung brand TV the exact model will appear inyour screen We will do a quick test of the LEDS and we see that the damaged LEDis on the strip below it's the last one on the right side This is the second time that in this TV model the damaged LED is in the same position We will see in detail the installation ofstrips these do not have screws They are secured with eyelashes made ofthe same chassis sheet they hold and press the strips As you can see in this part you can see a fold of the sheet that makes part of the LED strips does not sit well on its edges however the flanges are close to the LEDS and this helps dissipate the heat here you can see that they are close but .

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on the last LED strip below This tab is more removed from the LED and happens what I was saying earlier The heat generated causes the LED strip to bend and it separates from the chassis, this causes the LEDs to overheat For these cases in which the distance is greater between the strip and the sheet we will do the following here we see a card and this integrated circuit carries an aluminum heatsink at the top and in the lower part, to reinforce the heat dissipation They use this soft material resistant tohigh temperature and it is glued with adhesive to the card the card is being fixed orscrewed makes contact with the chassis blade also transferring part of the heat generated from that integrated circuit as we see here the distance is considerable we will use something similar and this we will do by applying high temperature silicone This supports up to 260 degrees Celsius let's apply it then on all the LED strips below and since we also replace the damaged strip we will fill with silicon in that area and we can fix it with a magnet giving the necessary setting time according to the specifications of the container and this will prevent overheating of that LED that's it in this video I hope you liked it, leave me your comments suggestions or some other idea to solve this type of failures and to support our community I wait for you in the next video, see you soon.

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