Illumination of the LCD panel with light lines. Repair of LED backlighting of the TV matrix UE32F5000AK. Edge LED: best color transmission

Hello everyone. Today, Samsung UE32F5000AK is being repaired due to the problem “the LED backlight of the matrix is ​​missing.” I rarely repair such TVs, because I have neither the knowledge nor the ability to repair such equipment. Proteus, once I got the nerve to try it, the master of the TV really enjoyed it.

So let's see.

Advanced TV diagnostics

When the TV is turned on, there is sound, but there is no picture. The TV responds to the remote control and buttons. If you are surprised, you can see that there are images on the matrix, but there is no LED backlighting. From this it is possible to conclude that the driver itself is faulty and the line of LEDs has burnt out.

TV selection

Having identified a possible discrepancy, we proceeded to investigate. Having placed the TV matrix on the table, first remove the stand, which rests on three bolts. Next, unscrew the 10 bolts around the perimeter, and then remove the back cover.

When removing the back cover, you must stitch behind the joystick cable, which must be removed, after which the cover can be removed.

The TB consists of three boards, and the life block itself, on the board of which there is a backlight driver, a main board, and at the bottom a board that controls the t-con matrix.

Significant malfunction

On LED TVs, all LEDs are connected in series. This means that if any of the LEDs are cut off, all LED lighting will stop working. As I said earlier, the main reasons There are two malfunctions: LEDdriver or else LED.

If the driver is faulty, then it is better not to supply any voltage to the LED. If the line of LEDs is faulty, then at the life supply terminal there will be a voltage of about 200 volts, or it can pulse from 150 to 200. This means that the driver is trying to light up the light However, it is important to use LEDs every day, and the driver is visible to the maximum. I especially understand this process this way.

Having taken the board to the life block, having determined that the life on the LED goes through D9101C to the capacitor, then measure it at a new voltage. Having connected the multimeter, it turned out that the voltage on the new one was between 190-210V.

This means that the driver is not working properly, and the problem is in the LED line itself. For me, the new thing is not very good, because I am even reluctant to take on the disassembly of the matrix due to the lack of information and the lack of minds for repairs.

Assembling LED RK matrix

With the motto “no problem”, the analysis of the matrix began. Prepare another table for the matrix, first connecting the cable from the LCD panel to the T-con board. Having looked at the TV in more detail, it was noted that the matrix itself rests on two frames, which are attached to clamps. I'll grab the frame. For this purpose, put the TV on the back wall, and step by step, starting from the top, starting to click the bolts. I would like to pay special attention to the damage done to the bottom of the matrix and to the bottom of the cable. The top frame came off very easily.

Next, adjust the matrices by placing the TV in front, with the cables facing down.

Carefully remove the matrices (decoder) from the slots so that the stinks begin to hang loudly.

Removed matrix decoder

I’ll tell you straight away that this is such a painstaking process that it made me nervous. Remove the decryptors from the zippers by taking the TV by the other frame and carefully lifting it up. The matrix was no longer on the table.

The matrix is ​​known

Place the matrix on another table and continue sorting. By clicking the frame on each other, removing the spit, which dissipates, releasing the LEDs.

Under the LEDs there is a white highlighter, which is held on 4 locking clips.

Having known them, you can take the spoiler.

LED backlight for TV.

As you can see from the picture, the TV matrix consists of five lines of LEDs, nine LEDs each. If we take into account that the skin LED lives at approximately 3 volts, then it seems that one line of LEDs for robots is close to 27 volts (3 * 9 = 27). In order to check which LED has burned out, first identify which line has broken the LED. For this purpose, through it is connected to a line with 9 LEDs living at 27V, and any line does not light up in this case and is interrupted. Next, through to the skin LED, turn on the 3V power supply and see which LED does not burn.

In my case, it was easy to identify the LED that was burning out, since it was already very hot, as a result of which the diffused lens changed color and slightly got better.

The temperature was such that the textolite on the gate side just burned out.

Having thrown in the lens, soldered in the LED. For this you need a soldering hair dryer. Apply flux to the animal, heating the plate from below until it is soldered. In this manner, seal the new one.

Rumors of a new LED, but still forgotten. Having been through several radio markets, in one of the stores you know similar LEDs, however, are already soldered. The person soldered it out of the TV, on which the matrix was broken.

I also soldered the LED using a soldering hair dryer. Having tinned the tracks, put the required pole on the new LED, and slowly put down the PCB underneath, until the LED is not soldered. It didn’t seal very nicely, because the white farb was angry, but it was safe.

Having applied life to the line, it miraculously lit up. Gluing the lens, which dissipates, folding the matrix in reverse order. Please note that during repairs the LED slightly changes in color, but in operating mode it is not noticeable.

Having finished folding, I requested the TV.

After spending 8 years, I gave the TV to the Lord. Varto note that such repairs are more effective for me, and I am even more excited about the result. It is possible that I have made some speeches incorrectly, please indicate them in your comments.

Other LEDs for LED TVs:

LED backlighting on modern TVs with screens made of rare crystals today includes a number of technological solutions. In an effort to increase the color temperature, for a better display of colors, manufacturers of displays for televisions have developed new lighting methods that are being developed with the use of high-quality LEDs.

RGB LED

To capture a wide spectrum of white light, they began to use a sub-switched triad of light-emitting diodes, which consist of blue, green and red colors.

There was an alternative to WLED with white LED and less coloration. The lighting system with three different light-emitting diodes is called RGB LED. The color gamut of screens with RGB backlights was larger, compared to the use of only white LEDs or the use of CCFL fluorescent lamps. There are also shortcomings: price, size, value, different hours, old LEDs of different colors, which over time led to discord in the color of the image. Therefore, RGB LED lighting was used on WLED.

RGB LED

WLED

Dependent on the limited RGB backlighting, TV manufacturers have relied on a variety of “white” LEDs. The stench appears either on the sides of the housing or in one mass behind the LCD matrix. With the help of special diffusers, light from diodes is evenly distributed throughout the screen.

Although we call such LEDs “white”, in reality they produce blue light when they pass through a yellow light filter and turn into white. Therefore, the use of white LEDs in screens back in 2010 gave a bluish tint to the image.

Over the years, manufacturers have colored the components, and WLED lighting has become completely practical, and even with respect to the light spectrum, there are noticeable disproportions in the colors displayed.

This color appears blue due to the blue LED. Vikorist light filters can be made lighter. And this filtered light is applied to the subpixels of red, blue and green colors to form the entire spectrum, surrounded by color deposits. Passing through the filters, part of the spectrum is lost, and the intensity of the flow at a frequency that indicates blue will be greater, less red and green. Using additional screen calibration, you can select the correct colors, and for other reasons allow the screen with WLED backlights to display only sRGB colors.

Since a WLED display displays colors close to blue (shades of blue), the difference in the spectrum of the blue color itself can put pressure on other colors that are mixed to create a similar color. Therefore, the appearance of shades close to blue may appear incorrect.

This problem occurred with the CCFL lamp, but the problem occurred with the green color. On the green itself you can see the peak of intensity.

Increased color fertilization

To expand the color gamut beyond sRGB and move to the current color standard, make changes to the WLED lighting.

And after the changes, the name GB-R LED or GB-r LED began to be used. Now, instead of white LED, replace blue and green LED, covered with a blue phosphor.

This technology allows you to identify peaks in red, green and blue on the spectrum.

This technology is currently being used in LG on AH-IPS matrices and Samsung on PLS. The advanced GB-r LED technology allows you to capture 99% of the Adobe RGB color.

Some video editors on their screens use another way to increase color. You need to combine blue and red light-emitting diodes and use green phosphors for the light filter. This technology is called RB-LED or RB-G LED.

I would also like to ask you to contact the “PMS” contact, which goes from the head board to the life block or, by extension, from the life block to the head board. Can't you figure out his role?
I don’t need to bother, because I also want to get into it. I'm hanging a monitor on a swivel bracket and I want to power it from a standard TFX housing unit in a case in which a new computer will be installed (with not very new components, with DDR3L memory and a 3rd generation Intel processor nya: ). Today I conducted an experiment by supplying 5V, 12V and minus from the floppy drive connector to the computer's life block. The monitor normally requested and turned on and beeped at the power button (I note that the PMS sends a signal to the life block about the shutdown of the inverter or the inverter and the head board at the same time). Simply hang the monitor above the bedside table and place it there, so it is much easier to power this type of life block, the more I put two phase switches into the life block, which simultaneously switches on the zero and phase (then the computer You no longer need to immobilize your yuter from sockets). And if you run a 220V cord directly to the monitor, then there are more wires, plus more hassle with switching on/wiring, and the CCD of the living unit will not be much lower (the amount of energy accumulated during the life of the computer living unit will decrease by ~5-10 V at) . Life unit with "GOLD" certificate, Sea Sonic Electronics SSP-300TGS Active PFC 300W. Therefore, I need to know how to trigger the “PMS” signal, since it won’t be critical if it is present on the monitor’s live block?

I also conducted an experiment with “PMS” today. This contact is supplied with 2794 volts and only when the monitor is running. If the monitor goes to sleep or the button on the front panel blinks, then “PMS” immediately drops to zero. And so it turned out that the first cat sees 5 volts 1.5 amperes, and the other sees 12 volts 1.2 amperes (for powering the headplate) and 12 volts 3 amperes (for powering the inverter). So, whenever the monitor is turned on or off, 12 volts disappear from both lines, and 5 volts are supplied for the entire hour while the monitor is plugged into the outlet and the main power supply supplies 220 volts to the power supply unit (perhaps 5 volts goes to the head board and suddenly the stench is needed to display the monitor in the wash mode.
So, what is more, for all the “PMS” it still comes from the head pay to the living block and it is necessary to launch a high-pressure cat, but you still want to know the expert’s opinion, which is why I judge only from practice and from logical assumptions.

And if it is possible, then I have three more lies before you.
1) You can’t see the 12 volts coming from the life block to the head board, it’s okay that 12 volts will be supplied continuously during the hour of sleep or when the monitor is turned off through the button on the head panel. As I have already written above, 5 volts are supplied to the power supply unit continuously, and the 12 volt axis is supplied only during the operation of the monitor. I just want to make sure that 12 volts does not damage the headboard when I am sleeping and the monitor is on.

2) Based on the system unit, I want to implement LED switching with brightness control behind an additional exchangeable support in order to eliminate the PWM of the diodes at low brightness (interference). I understand that the rooms will heat up more, resulting in CCD (slight increase in energy absorption), but the health of the eyes is more important. I myself don’t know how to properly unpack the changeable resistor that needs to be placed in the lance due to the tightness. According to the printer, the accumulated energy of the stitch is 9.6 watts per meter. The stitches are cut at a distance of 5 cm, and my matrix requires two cuttings of 45 cm, for a total of 90 cm. And according to the manufacturer’s claim (which I don’t even trust) it works at 12 volts 800 milliamperes per meter , minus 10 % = 720 milliamps. It would be better to use a full supply of power, preferably 2-3 amperes. So, I would like to put an additionally variable support in the lance, so that at maximum brightness (where the changeable support feeds the food directly), the output would not be 12 volts, but 10.5 - 11 volts, no more. It is necessary that the LEDs do not overheat at maximum brightness, and thus increase the term of their service, so that the next time I disassemble the monitor and matrix box, I am still satisfied.

If it’s not easy, write the number or model (I don’t know how to correctly) of the replacement support (it is necessary with a handle, as with the flexibility of acoustic systems, because in the back of the monitor there is a place where it can be indicated) and how many ohms (Navit lower kOhm) and Watt use a “simple” source, which further reduces the voltage from 12 volts to 10-11 volts.

3) It is also necessary to know the location in the main board where you can get 12 volts for the power supply, so that the power supply disappears when the monitor is turned off from the switch button and to sleep mode. I myself can use a tester to find out 12 volts, which disappear when the monitor is turned on and asleep, but I’m afraid that the stench will pass through any resistor or transistor, which can burn out due to the additional supply of 0.7-.08 amperes.

For many years I have been choosing the most compact computer with standard components (a standard power supply unit, a standard motherboard, a processor, VP memory, apparently a laptop DVD drive). Having installed the "RESET" button on the peak, which rejects the indicators, replacing the poor black indicator of the computer with a warm orange one, installing the DVD drive (so that there is no noise unnecessarily when the computer is turned on) and powering up the speakers, and also attaching to the peak there is a booster and a tension regulator. It was impossible to wait until the anti-filter filters arrived on the housing and the housing unit and the 6-pin connector for removing the speakers from the housing and indicating their operation. I plan to screw the speakers to the bottom of the monitor body, and display their indicators on the bottom of the speaker body (at both times the lower plexiglass will light up). I’m already glad that I lost a little hemorrhoids before the completion of this Frankenstein, and then I’ll call and say that the monitor has stopped working. The delay was very strong: (
Therefore, I want to do everything as reliably as possible, so that it works for a long time and does not cause any more trouble.

P.S.
Thank you for the poor food, I’m just afraid I’ll unknowingly burn the monitor’s main board. Doctors, that this model has not been released for more than 10 years (and as I have already written, there are no alternatives to it, because currently there are only two models on IPS matrices, on VA it is already a long time ago, especially on PVA), but buy the same B / In a good situation, it is practically not possible (in Moscow and St. Petersburg they rarely appear for sale). If you buy it remotely, you will be able to see any dark spots or stains on the matrix, as well as bits or burnt pixels. If I was swimming through the AVITO another 2190UXP, seller of piper, singing a matrix in Ideal, and if the Monitor Pruhav, wagged with a ny lamp, pushed at zero (Mabut, selling it, the nun has not taken off at the nyoye) ib yak bonus. I removed two bits of pixels (fortunately, the pixels are not in the center of the screen and on the VA matrix they are not so noticeable, their fathers do not mark them).

One rare crystal monitor BENQ FP93G-X is alive, faithfully and truly serving its master for many years, delighting him with beautiful images. A couple of months ago it had a problem - it would turn on every once in a while, then stop turning on completely. seconds and soak in. The diagnosis is uncertain - the CCFL lighting lamps have exhausted their service life and are exhausted. Instead of purchasing a new monitor with a larger diagonal and storing a few more in stock until the shortest possible time. To revive it - replace the lamp illumination with a light-emitting diode.
I’ll tell you straight away that this kit only requires a driver, and a light-colored one can be stuck in some sort of self-destruction.

Delivery and morning pickup

Driver testing

Before installing the driver into the monitor, test it. For this purpose, I connected it to the 12 volt power supply unit, through resistors 47 to whom I connected the ENA and DIM connections to the power supply plus.


Next, a two-meter axis of such a light-emitting strip was added:


І connected to the driver instead of the standard equipment. The ENA wire also has a 120 kohm changeable resistor added to regulate the brightness of the glow. The driver runs 2 meters of LED strip without any problems. Maximum brightness:


Minimum brightness:


Having screwed up the driver for so many years, nothing got hot on the board.

Driver installation

Further, the monitor is used for disassembling, during the time of disassembling the work, it is not necessary, since this process requires accuracy and the instructions from disassembling the PK monitor can be easily known, for example, the axis
If CCFL lamps were detected, their examination confirmed the initial diagnosis:


The mounting profile of the CCF lamps had 2 light-emitting diodes glued in - they fit perfectly in terms of width and had good wiring in the name of life.
Then it was necessary to turn on the high-voltage power supply, as it was no longer needed.


Through this, a voltage of plus 30 volts was supplied to the inverter, and now you will need to use it to liven up the driver.
We glue a piece of insulating material with a radiator onto the metal base for a 12-volt CRANK - since 30 volts are rich, we use it to stabilize the voltage:


We glue the driver onto the hustka, install the KRENKA onto the radiator, connect the darts to the power supply unit, solder the darts from the feed directly onto the driver board:


The ENA and DIM connections on the monitor's life block board can be easily identified with a multimeter.
We install the life block and connect the driver life:


We cover everything with a metal screen:

Final test and revision

Let's turn up the monitor and warm it up:


Pratsyuє! Upon careful examination of the image, no illumination or color interference was detected.

Pros:
1.Good external appearance and neat soldering.
2.Price.
3.Easy to install.
Disadvantages:
1. There are no openings on the driver board for mounting.