Let's Fix: LCD Monitor LED Backlight Upgrade
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- Опубліковано 19 лип 2024
- So surprise surprise, my main monitor (an LG Flatron W2240T) I bought for dirt cheap years ago is finally crapping out on me. The symptoms are it randomly shuts off and then on again after a couple of seconds repeatedly. At first I thought it was the caps in the supply but they are good and it turns out the ccfl tubes are going so instead of just buying new replacement tubes how about we go green and see if cheap LED kits off eBay are worth the time and money. I show the general installation process as well as some roadblocks I ran into.
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I'm in your same exact position 6 years later, also it's crazy how you're still liking comments.
My monitor failure was more bizarre, whining while slowly flickering more and more for 4 minutes until it shut off. Took me a week to diagnose, failing CFL tubes will generate ozone and it smells like 9v batteries. So maybe the inverter is failing too but this fix will bypass that anyway. Good luck on everything, thanks for the great stuff
An awesome starting guide to achieving this upgrade!
I recently bought a very nice 4:3 UXGA (1600x1200) HP LP2065 IPS monitor from 2006 and its aging backlight already clocked in at 18,500 hours of power on which brought down its brightness to 140 cd/m^2. This monitor has 3 CCFL's on the bottom and 3 on the top and has a thick plexiglass waveguide to allow a lot of light to pass through because IPS panels block more light than TN panels.
Before starting to upgrade this monitor I practiced the upgrade on a cheap TN 5:4 SXGA (1280x1024) panel using this video and was able to increase the brightness from 160 cd/m^2 to almost 400 cd/m^2! Then I tried the upgrade on my UXGA monitor aaaaand.......increased it from 140 cd/m^2 to 160 cd/m^2. I was not happy, so I thought, hey, why not install a second LED kit to drive 2 more LED strips so I have 2 strips on the bottom and 2 on top. What do you know, it worked! It now has a brightness of 325 cd/m^2! Woo!
Very informative and probably the best video on youtube regarding CCFL to LED conversion.
The first video that actually explain everything, now i will finally fix my monitor, but first waiting 2 months for the kit to arrive. Very well made video thanks.
Thanks!
Never fails to amaze me how often I end up on one of your videos when I'm researching a project... Just what I needed to know for my iMac project!
awesome. I have a 23-inch E2341 which started to experience random backlight issues (first it was a corner, then switched to another corner and now it turns on backlight for a split second before going dark. This has encouraged me to try to fix it myself. Thank you, outstanding explanation.
Fantastic indepth explanation. I realize this video is a few years old, but I'm doing the exact same thing on an older Benq 24" monitor and this video explains everything perfectly! (The instructions that came with the conversion kit were totally confusing. Great job!
Finally... something that's not in Hindi. 😣 Thank you.
I understand both 😉
I'm Indian and even I agree 😭🤌
I was looking for a way to perform this on a laptop.
Your video has explained the basics well enough that
I can do this now.
Thank you for the help.
I love you man. Your vid helped me a lot.
Probably best vid about the LED upgrade on youtube.
Good detailed video showing each and every step along the way. Thanks for sharing.
Useful video. I have an old LG 3D monitor and it has trouble firing up the backlight. I put it to one side for a while but this sounds like a real way to bring it back into service.
Just FYI, the four colour quad in the top right on the RPi, which on later boot loader versions is a little lightning bolt, is a low voltage warning. I have found that I need to supply about 5.4V to avoid this.
Very nice "just take your time" made video with a lot attention to detail. Very good. Thanks for sharing!
Thank you very much for this tutorial. Very informative and interesting. Cheers!
No doubt this article has to be one of the best, if not the best instructional. thank you very much.
I have been trying for 8 months . (off and on)
I hope I can get some assistance with further instructions on converting my HP2509M Hewett Packard monitor There is no silkscreen depicting different connections at cable from power board to main board. I have tried different main boards and power boards, one of which I removed transformers and daughter board, with same basic results. I for life of me cannot find a suitable + 12 to 35 v to power inverter. The inverter board will remain powered in a standby state for 24 hours. When I turn monitor on, the add on inverter board might stay powered for an hour and then loses power. I am using a power source drawn from a cap that is emitting 32 volts, and then this source drops out.
Super tutorial. I would add to be extra careful when handling the LCD panel. I came sooo close to fixing my monitor but, after turning it on with the new LED's, there is a small crack in the LCD panel which renders it gone. I feel like I lost the patient :^(
Awesome job. Very informative. great instructions. thanks. will be doing these conversions.
Hello. I saw the video very good. I'm also preparing to change the old lights on my LG screen and I bought them from Ebay and I'm waiting for them to arrive. But I have a question why did you put the lines the cables ie from the other side and drilled holes?
Very helpful...thank you for your time well spent!!😎
Hi! Nice video, I made it on my lcd monitor, but it have a 12v pin instead of 22v that you have. I put on it the driver's positive and it actually worked, but the brightness is very weak. Maybe need more voltage? Any other idea? Thanx
Good job. Thank you very much.
very good solution, you will have the scheme of where to connect each thing each pin or voltage
Unfortunately unless you have the exact same monitor as I do, providing a specific wiring diagram would be useless. I tried to explain what each pin does so anyone could adapt the mod to any monitor.
Thank you very much brother..
I installed the LED strips in my Samsung 2494SW and it worked with no buck converter needed as the board has a 15v pin, but the LED strips are dimmer than the CCFLs they replaced. The strips come with style 3528 LEDs and a new pair I bought on ebay have style 5630 LEDs so maybe those will be bright enough. I really need at least 250 nits, with the current LED strips I'm only getting 140 total nits. If you have a suggestion for me on what went wrong, or if I should expect the low brightness from the 3528 LED strips? edit: The seller told me you can replace the resistors with lower rated ones to get a higher amp output. I will look into this and come back later.
20:30 since the cable has plugs that only fit in one way, no matter what end you put in, the other end would still have the correct signal go through the correct wire, even is he colours would not match
Very nice explaination !👍👍
Good evening , i have a t27a750 3d Samsung monitor with a LTM270HU01 Samsung screen and the bottom right leds are falling. Do you know if this led kit you used in this video will work for my monitor? Thank you in advance.
Very instructional. I wish I would have watched this prior to converting my old ViewSonic monitor to a panel light. When it failed, the monitor would flicker for 5 seconds and then turn off, and I assumed there was a problem with one of the circuit boards. As replacement monitors are cheap enough AND I really wanted to try turning a monitor into a lighting panel, it didn't seem worth it to try and troubleshoot the boards. But now... after watching your video, and you describe your monitor shutting down, I'm guessing the CCFL tubes simply went bad and there is likely a safety feature to power down the monitor if the inverter powering the CCFL's is seeing fluctuations on draw/resistance? I still have the CCFL's because I'm not sure where to dispose of them locally, and by examining them I can see that 2 of the 4 are very black at one end. Had I considered that the monitor might completely shut down simply because of bad CCFL's (as opposed to just going rather dim), I would have taken more care in disassembling the monitor and tried your solution to see if I could resurrect my monitor with LED's. Oh, well... I DO now have a very nice panel light, and the experience that goes with converting it, so there's that...
If you want to use the original circuitry you'll have to reverse engineer enough of it to figure out how to trick it into staying on. Clearly it's detecting there's no lcd attached so it's sending a signal from the lcd controller board to the inverter/power board and shutting off.
@@VidarrKerr In my case, I actually stripped out all of the original lighting (fluorescent tubes) and electronics and substituted my own. Basically, I just lined the cabinet with standard LED strips connected to a 12V power source and dimmer switch. The only parts of the original monitor I used were the cabinet itself and all the screen layers (except for the LCD panel). I tore the rest out.
Yeah long term leds are the way to go, plus they are easily pwm'd if you want to control brightness.
@@NorthernKitty Oh, I see. OK. I already have both LED strips and a pile of 12V power supplies.
I stripped both of the panels all the way down to clean them and everything was looking 100%, so I wanted to recycle.
But, it was becoming such a pain to get it to work. I had built a little circuit with resistors and transistors to "PWM" the power to the driverboard to trick it, like sjm4306 said, but it was a total fail every time.
Thanks, I will go with the LEDs. It has been 6 months that these have been sitting here not working. LOL.
THANKS BOTH OF YOU!!!! Awesome videos BTW, I watched several more last night!
@@VidarrKerr If recycling is your primary goal, sometimes you can still desolder and recycle parts right off the original electronics - capacitors, connectors, wiring and such. Even the metal chassis can come in handy for re-use. Also, if there's a place nearby you that recycles electronics, they'll take whatever is left over to melt down and recover the metals (like copper). There are usually recycling centers in most highly populated regions. If not, sometimes local health departments or such will act as an intermediary to collect parts for recycling, but maybe only a few scheduled times each year.
Thank you for the video. I'm using a guitar floor stand for my monitor (that came without a stand) and it works perfectly. You can buy a new one for under 10 bucks (I've got mine from Thomann) or a used one for less than 5 $
Thanks for the video. I suggest you to update the links as I was about to order a kit but the link led me to 404.
With you saying the brightness is not as good as CCFL, do you think more expensive kits could deliver more light?
I had the opposite experience, the retrofitted 22-inch monitor got brighter than it ever ran. But the colour was horrible.
But i had done a little trick. I noticed that at the rather substantial drive current, the resistance of the strip PCB becomes substantial, so i terminated it from two sides with an extension wire. Positive rail terminated at one side, negative at the opposite. This way the resistance is evenly distributed, and the LEDs probably run more efficiently overall.
Nice tnx for the pointers
@sjm4306 I have a Gigabyte 32" Monitor G32QC and I need to replace one of the light strips since I have a black bar meaning one of the back lights went out. Can you tell me the part number or a link to the backlight strip that would work for my monitor?
Good work.
I got a 24 inch onn tv I want to find thinner LEDs for it to light the screen where can I get some
Very helpfull brother.. keep it up.. i love you
How to know where to find 12v and to solder the yellow wires. My mainboard has no text like yours
Awesome! I am about to do this. But, I have another two monitors that are completely broken except the backlights and the glass. I want to use them as light tables, but I cannot get them to stay powered on.
I plug them in, they light up for a few seconds and then they turn back off. Even if I turn the monitor power on, the backlights still don't stay on. Both of those have CCFL tubes and I cannot find how to power them. I need to find a way to keep the power from the inverter to stay on. I had no idea it was going to be so complicated. These make very good light tables if I can get them to work.
It may be easier to use those replacement laptop ccfl inverter modules and power them from a 5v power brick
@@sjm4306 I am going to do the LEDs like you and the other guy did. I give up with the transistor hacking. I will have to find a recycle for the 8 CCFLs. I live in Brazil, so it is kind of a problem.
My question Can i upgrade My HP DV6000 laptop LCD screen with LED back light because it is very thin in size just 5 mm maximum it 14.4 inch LCD screen
Thank you I can fix my monitor with this video
Did you see the "new" display of Sun Vision "Featuring RLCD Technology" ?? Are you able to replace the backlight with a mirror or any other reflective material to convert/make own RLCD ? some kind of DIY.
With a normal lcd I'd figure it'd probably be too dark, so it's possible sun vision uses specially designed polarizing filters or the lcd itself is more transmissive.
@@sjm4306 mm I think is the same LCD, without the upper filter and with a ultra white backplate. I'd love to know how a white sheet painted with "White 2.0" to replace the backlight, would look like.
Great. thank you..
Help needed please.
Opened up my old Samsung SyncMaster 2494HS and sure enough, the bottom CCFL is busted.
I want to try this fix and convert to LED strips but I have no clue which pins need to be connected to the yellow wires?
Mine has a 15V pin which is ideal (LED driver accepts 10-30V). And it has multiple ground pins so I can connect those. But my board doesn't have a pin clearly marked as "INV" so I don't know where to connect the yellow wire?
The power supply board has these pins:
1
B-DIM
15V
GND
GND
GND
5.2V
5.2V
DCR
ON/OFF
3.3V
LED
KEY1
KEY2
GND
14
I suspect it's the ON/OFF pin? Or would that be a pin to turn the monitor on or off when touching the touch control buttons on the front?
The inverter board has these pins:
PWM_DIM
+13V_IN
GND3
GND4
FUNC_GND1
+5V
+5V_IN
A_DIM
BL_EN
+3.3V
LED
KEY1
KEY2
FUNC_GND
Any help is much appreciated!
EDIT: I think I've found my answer on another video watch?v=jMh-PCfehQI
It's been a few years so my memory is a bit rusty but iirc the inv pin is basically a digital logic level enable to turn on the backlight so the closest thing looks like the signal called BL_EN which would be backlight enable.
Amazing video. It helped me bring back to life a monitor that was sentence to death in a landfill (not by me). I connected the cables as you instructed and it worked perfectly. With that said, I'm having a unique problem... after 4 days the back light won't turn off when the pc is powered off. I have to cut the power to the monitor complement. Any suggestions? Thanks
I'd start by checking the wiring going to the enable pin of the led driver. Something must be keeping the driver enabled and thus it stays on.
@@sjm4306 thanks, I'll check it out!
Thanks for the great video on this topic. I would like to do this to a VIZIO 47" TV. But I can only find 24" strips (540mm) online (EBAY). Is it possible to run 2 kits in parallel?
If you use two separate led driver boards in parallel it'd work. You could alternatively use one driver and two led strips in parallel but they would have roughly half the full brightness.
@@sjm4306 Thank you for the reply. You have been a great help.
The TV probably isn't built the same way? I don't think they're edge lit with CCFL, they usually have some sort of light box behind the display. I think i have seen people simply strip the box and lined it with bog standard LED tape and driven it from whatever 12V supply they could fashion. I imagine, there can be a 12V or somesuch rail in the PSU, from which the CCFL driver is powered, rather than directly from the mains, at least this has been the case in the monitors, never made an experience with a TV before. Obviously the rail is easily powerful enough once you disable the CCFL drive circuit.
would it be possible to convert a monitor like this to work off of DC power after installing the LED backlight? would it just depend on installing a new controller board as well? I'm trying to convert an older VGA-only LCD Monitor into a portable HDMI monitor that can run off rechargeable lithium cells
The controller boards in these lcds only need 12/24v so yes it's possible to led mod them and just remove the power supply board so they can directly run off dc.
I finally got that led conversion kit here in south america; my Dell 22" lcd died 2 months ago so I'll follow your tutorial to see if I can convert it to leds; one thing I didnt see is your brightness control working; Im not finding any pin in the old monitor controller to connect the led controller into; maybe one can connect a pwm generator to that pin independently? something with a 555 or similar?
Yeah a 555 would work, or if you dont care about turning brightness down you can just permanently connect it to vcc for full brightness.
@@sjm4306 Thanks so much! subscribed!
Is there a way to tell easily what length LED strips I need or do I need to open it up first and measure the CCFLs to be sure?
They sell the kits at the right size according to the diagonal screen size
Nice Efford.
Do you think it would be possible to put more powerful leds in? Could be great mod to turn old screen into a field monitor or something
dude ım looking this answer, but I didnt see anyone did this. ı will find some rubbish screen and try.
The only limit is PSU.
So you soldered the wires instead of just plugging them in. Was there a good reason for this? Where were they designed to be plugged in originally as I don't see a spot for it on the PCB
I had to solder wires, the kit is designed to be generally universal and my monitor doesn't have that random connector with that exact pinout so there is no way to just plug it in as stock. I also had to go the extra step of adding a step down converter anyway as my monitor only supplies ~22V instead of the 16V max the led controller requires. This step may be unnecessary for some monitors though if there's 12-15V available internally.
Was there a reason you didn't run the wires out the same side as the CCFL's?
Rodville The high voltage side of the ac input/inverter was on that side and the wires were too short to run to the other side where the connector on the supply board was. The simplest solution was to stay away from the right hand side of the converter.
The connector wires would just be swapped. the connector on the other side would also be backwards so it would just make black V+ and red gnd on both sides
I have an apple cinema display that I want to fix and it has this issue, do you think that this kit will work on a monitor that has only one strip? In my case only at the bottom, thank you
It will probably only be half as bright if it only has a spot for one strip.
@@sjm4306 It's not actually half as bright. The driver just rams the full 9.5W of power into whatever you happen have connected. The two outputs are in parallel to each other. If it's one strip, it'll be receiving twice the current. It seems likely that the endurance of the strip will be shortened, and it won't be quite as bright because efficiency is lowered with temperature, but you do get a spare then...
Surprised it'd run the output at constant power and not the industry standard constant current that most drivers use.
@@sjm4306 technically constant current. But since this goes into a 3-series matrix of white LEDs on the output, no matter how you connect the strips or where you cut them, it comes out to about the same power.
Hello... cuold you share info about the V+ adpter / Driver you used..? Thank you..
It's a common cheap adjustable buck module I bought off ebay, should be easy to search and find the specifications in the sales description.
Orientation of that cable actually does not matter. No matter which plug you use on the driver board and the one on the monitor, the pinouts per cable are the same.
Well I had same problem with delivery ... it came bend in my mail box ... So I am asking what type of battery tabs did you use ??? :/
I used nickel strips used for welding rechargeable battery tabs (any wire would actually work so long as it isnt too thin but also not too thick)
Hey man. Thanks for your video. Just wondering if you have any idea as to why the dim or brightness adjustment isn't working? I was able to make the LEDs work despite only having 5V by using a boost converter. But right now, the dim or brightness adjustment doesn't really make that much of a difference.
To adjust brightness you need to connect the pwm pin of the original backlight controller to a pwm input of your new backlight supply.
@@sjm4306 Not sure I follow. My Dell board only has on/off, dim, 2 5vs, and 2 GNDs. So yeah, only 6 wires that connect the main board to the other (logic?) one.
So I'm assuming that just connecting the DIM wire of the LED driver to the DIM of the main board won't work?
Oh, yeah dim is bascally a pwm digital signal used to control brghtness
@@sjm4306 Following this logic, so connecting the DIM wire of the LED driver to the DIM of the power board SHOULD work, right?
Yes, I think it should work unless if it's some other non-standard signal like analog, 1 wire, etc instead of commonly used pwm
hi, nice informative vid! my prob is my dell board only has 5v. should i use a tester to search a 12v supply or should i just buy a 5v to 12v 8w step-up module? thanks
Use a multimeter to (very carefully) probe for a 12v power rail. Even with 5v through a boost converter you may brown out the logic rail since even more current will be drawn due to how boost converters work.
okay, i will just look for a 12v then. im also doubting a step-up circuit. im just wondering, if the board only has 5v out, does that mean the cfl was running just with that voltage? or is it using a balast like the old cfl? thank you very much for your help.
Ccfls need a balast/inverter because they run off high voltage
hi, i got a 14v supply in the board and had the led working. but when i plugged it on the pc, when it is starting up, all is okay, but when i reach desktop, the screen tends to be crazy with lines which looks like distortions. i think im drawing some power from where im not supposed to. any tips? thanks.
Hey. Using a Dell monitor here as well (only has 5V). I was able to make it work by using a boost converter (as he suggested earlier).
Great video! Any tips on how to identify the pins if the sadistic manufacturer thought it would be prudent to not label them?
Visually trace where the wires go. If you are lucky they will lead to a chip which you can look up the datasheet to figure out what the pin functions are. Otherwise you can measure the voltages on the pins to figure out if they are supply or control pins.
@@sjm4306 great! Can you be more specific about how to find which pin is which?
Could I possibly do a same or similar upgrade on a 22 year old LCD monitor?
Sure, no technical reason this mod wouldn't work with any lcd monitor
hey, is there a way to convert a monitor to take power directly from DC? Like in LG monitors? Simply bypass the inverter from 220 (or 110) volts and use the required power in DC? Benefit is huge - u can power ur monitor from a power bank.
I got an upgrade of my monitors from 22inch LG to 27 inch dell - Dell S2721DS but those dells connect directly to 220 volts outlet. What the shit. Now I cannot power them from power bank, or if powered from Bluetty power station, there is only an option to power them from a AC plug. Which means doble conversion of power. Which is unnecessary and inefficient.
Monitors use only 15 W of POWER. It's same as the old monitors, but can't power them cuz there is no DC plug on the monitor... So, I'm searching for a way to bypass the innate converter and supply the DC power directly. Any experts that can help me please?
It's really necessary option for Ukraine.
Theoretically every monitor runs internally on anywhere from 12-24V dc. I say theoretically as some models may also need a separate 5V rail for the logic (which can be simply generated from 12v with a buck converter). Older ccfl backlights may need to be led modded or a separate 12v inverter module provided.
I don't have 12v at my power card output. There is 5v. As you said, we will search for the appropriate voltage on the supply. Is there necessarily 12v on each power board ? .should i look for 12v on the board surface ?? . because I have 5v, graund, ena and dım on my power output ..or do i have to use step up converter for to obtain 12v? . thanks in advance for your reply
You can try it with 5v but I think I tested that the leds wont light up with less than 10v or so with the led driver I used.
@@sjm4306 no light up with 5v. what is the solution ? :)
Then yes you will need 12v with something like a boost converter
@@sjm4306 thank you very much
going to try reviving an old eizo lcd I got for free with one of these
Do you have pictures of the broked led bar repair? Mines unfortunately arrived broked too.
I don't think I took any at the time and unfortunately I'd have to completely disassemble the monitor I am using right now to take them. It's really not complicated though, all I did was scrape away the soldermask on traces that were disconnected on both sides of the break and solder wires reconnecting them.
@@sjm4306 thanks for the reply, there are copper traces on both sides of the PCB?
IIRC I only had to bridge traces on one side, but may be different if they changed or revised your pcb.
Changing a monitor from lcd to led improves image quality or something else?
It's still an lcd, I'm just replacing the old burnt out ccfl tubes with more energy efficient leds.
Hey, you left out probably the most important part of this video! I'm doing this as you show on my Samsung 2233 monitor but you did not show how to know which are the DIM and ENA connectors?
Because every monitor pinout is different. Mine were labelled right next to the pins but yours may not be or may even be on completely different pins.
Good morning, help please.
I have the same Kit and also a LG W2043S monitor, I did exactly the video, except that I connect the direct positive to 22 volts (in theory it works from 10 to 30 volts).
I turned on the monitor and it works, the problem is when I press turn off, it does not turn off, it only reduces the brightness to a minimum, but it stays on all the time, I turn on again and the intensity of the led increases.
Would you know why? I would appreciate any help.
Check the enable and pwm inputs to the driver, for some reason it appears your backlight isnt being disabled. Use a multimeter or oscilloscope to see what they are doing during the on an off states.
In the off mode it shows 22 volts, in the on mode it shows 22.2 volts.
For what pin? Enable, pwm, Vcc?
drive.google.com/open?id=1OSorOt4HZshAhQQ0FZuCn1j_jDmGL14n
Have you done a video on repairing/cleaning an original GBA model yet?
DantheLazy Munchlax782Gaming The closest was a video I've done on 101 backlighting a gba.
okay thanks
oops, I did this for a laptop I got back in the early nineties when laptops cost a fortune and I wanted a laptop badly back then so bought one that someone thought was non-recoverable/broken for cheap...I didn't know they had mercury in them. In fact there was no internet as we know it back then and I ended up buying new tubes from an electronics fleamarket and just chucking the cooked ones in the garbage afterwards. Got the old laptop working though despite not knowing what the heck I was doing.
808v1 The amount of mercury is tiny as it's in the form of a vapor so it's not the end of the world but it's best to be careful.
Does every LCD monitor need a bridge between GND and "inwerter on" to keep the unused inverter off?
It really depends how the circuit is designed. I just tied it to permanently disable the inverter to make 100% sure it was off for safety. Logic level inputs shouldn't be left floating or they could oscillate between both states or activate something that shouldn't be on. Alternatively a pull down resistor can also be used to achieve the same goal.
But you "liberated" the wire from the connector on the power board and soldered it to the ENA input on the LED power supply. Is it not enough to keep the inverter off? I'm not so good at understanding electrical schemes. That's the one for my monitor. elektrotanya.com/samsung_2443bw_bwx_nw_chassis_ls24myk_ls24myn.pdf/download.html
What resistance would be appropriate? 10 KOhms or something like this?
The enable wire I disconnected was from the data board to prevent it from controlling the inverter and from the power board I shorted its enable pin to ground. Yes a 10k across enable and ground on the power board will work just fine as well.
OK. Thank you a lot! I'll answer how i would have managed as soon as my LED kit will arrive.
Finally my LEDs arrived and i found some time to take care of things. I connected the "enable" wire as shown in this video and put 10KOhm resistor between GND and "enable" pins on power board side. The LED's are shining nicely and nothing burned by now ;). I only have a smallproblem with the dimming control because my monitor has two wires connecting power board and IP board. One is described as BL_ADJ_PWM the other as BL_ADJ_ANALOG. It's obvious that BL_ stands for "backlight" and ADJ_ for "adjustment" but what could be the PWM? I guess i should connect it to the analog output, because the led powering inverter has a 0-5 V regulation.
Unfortunately after a long wait to get to this project , the backlight doesn't power up: (
Thanks anyway, very good video.
Whether the LED Stripe can be cut? if it's true on how many diode?
You can visually inspect the light strip to figure out how many of the leds are in series (my guess is 3 or 4) or just use a multimeter to figure it out (by measuring continuity between adjacent leds).
@@sjm4306 OK, I have not Buy kit so I do not know anything, I have 23 "LCD I would buy for 24" LCD, so I thought I cut off the surplus to work for me.
Sorry I cant be more helpful, both of mine are inside my monitors so it wouldn't be easy to find out.
Does miniled monitor have same led strip design?
Nope, miniled is completely different. It has the leds arranged as a digitally controllable matrix pointing towards the screen instead of along the side. It's controllable so that the main driver chip can do local dimming.
What I have to search for on ebay to find the small board where fitting the ccd strips?
I think you mean the led driver for the led strips?
Yes incredibile. What I nave To search dir And The where I nave To Connecticut. Thank You. Ad Soon as possibile this week I'll seme You some pittura.
Pietro
Sorry for my previous uncomprehensible message it was because of the Italian typing system.
Yes indeed I referred to the led driver for the led strips. I also need to know where I have to connect it. As soon as possible I'll send some pictures of my disassembled led screen and boards. Thanks again
Pietro
Oh and nice video
Sir. What will happen to lcd monitor.. if run it morethan its recommened resolution.. now my monitor is not working.. no power. No out put power from its smps.. which part is chance to damage. Any idea sir??? Plz help me
You cant really run a monitor at a higher resolution than native. For instance in windows it wont even give you the option of higher resolution than the panel is capable of. Your problem is hardware not software. Your smps is damaged and needs to be repaired or replaced.
@@sjm4306thank you sir..for your quick reply. actually i used it with tv tuner..as tv...
Either way pretty sure its definitely a hardware problem with the power supply
Thank you sir..
First of all, this is a very good video. Very well made, everything is in focus, and you were very descriptive as to your actions. You took the time to explain the caution points performing this upgrade. Having said that, there are a few safety concerns with your replacement procedure. Double sided and electrical tape are not appropriate for this repair. The default human behavior is to be lazy, obdurate, and forgetful. Given that heat softens glue and the location of repair site is visually obstructed from incessant (or even periodical) visual inspections without a teardown/dismantle, your repair will fail. WHEN that buck board falls and shorts to the ground plane, the magic smoke will let loose it's mystical powers. If you get extremely lucky Emma Watson will show up with her wand and all will be MUCH better. Unfortunately I foresee the fire department showing up in her place. My suggestions are too long to post so I have to make another post, I'll comment this one.
Many videos on this subject are ambiguous at best -- incompetent fools wielding precariously modified multimeters. They are laden with perilous regard for personal safety that is so abundant that you can almost see the Death Eaters circle in the background (I couldn't resist). This video was saturated with rich informational content, devoid of marketing gimmicks and exhaustive YT subscription requests. I hope you benefit from aforementioned suggestions, however you take them. I enjoyed watching this; Keep up the good work.
Thanks for the very detailed comment! Absolutely spot on from a safety standpoint, I was just a bit lazy, cutting a few corners.
My suggestions are as follows:
(1) Use standoff/screws for the boards and drill/tap if necessary. Add thermal interfacing at the chassis - boards junction. [safety/component longevity.]
(2)Use a smaller gauge wire and re-pin the logic connector with a 2 wire to one pin instead of soldering. This would allow all of the boards to be removed and replaced easier.
(3) Secure wires mechanically when possible, mountable zip ties are awesome for this. If not possible or practical, use Kapton tape (the yellow stuff on the table at 12:05). Cover all wires with a shielded braided wire loom or shielding tape [assists to mitigate noise/interference]
(4) Use rubber grommets for wires through chassis. The unbearable carnage and sharp edges left behind from the Dremel warfare will wreck wires and the interference/noise shield. [easier/faster/cleaner/safer: vibrations wear wires, remember some places are prone to seismic events.
(5) Apply high-temp hot-glue to all connectors just before closing up. Helps to mitigate Old age, UV degradation, earthquakes, etc. [Safety]
(6) You should have inspected the other sides of the boards and looked for failures and hotspots. It' better to just replace all caps when practical (including on the new led driver board you have). Repair, replace, resolder, and rework all components/joints necessary and clean up board. Repair the conformal coating(s) if applicable.
(7) Disconnect any unused CCFL HV boards/components. [Save energy, prevent inevitable failure]
(8) Anti-static mats are cheap and effective. Luckily nothing was harmed. Wear some nitrile gloves when working with the screen and LEDS so there is no risk leaving oils behind.
@@sjm4306 Sorry YT Truncated it. Edited to repair.
@@Cameron_J Could you please explain what do you mean by _add_ _thermal_ _interfacing_ _at_ _the_ _chassis_ ?
@@I967 mcpcb/drivers/transistor heatsinking.
I had done an LED retrofit with same looking kit on a Philips 200WS monitor several years ago. I too had to perform some repair on the strips, they weren't outright broken, since our mail is nice, but some LEDs in the middle weren't doing so well. I don't think the stress of being handled did them good, i think the solder joints or bond wires within the LED enclosure had become unhappy.
The result was unsatisfactory colour. Way too blue. Correction was applied in the LCD menu, but it's not ideal because many of the underlying bits of the panel resolution are unused across two channels, especially blue. Also linearity is worsened, due to how the monitor applies correction - not very well. How's the colour working out for you?
Now i have an Acer AL1722 where i want to perform the retrofit again. This time the kit was slightly more expensive to order, but came in a piece of PVC conduit, suspended in bubble wrap, adequately protected. Still, on low current, i can see that i should replace at least one LED, the LEDs just aren't matched very well. Besides, i measure the colour temperature, and it comes out to about 16000K. Even when run at very low brightness, it's significantly more blue than other cold-white LEDs at hand, and easily reaches 10000K at levels needed for the monitor.
I'm thinking of ordering 6000K or 7000K LEDs, heatgunning the LEDs off the strip, and soldering new ones instead. I'll probably extract the CCFL tubes that still work and measure their colour K. I now have a little laptop CCFL driver board so i can fire up one tube. I looked around and replacement CCFL seem to list about 7000K range.
I measure colour temperature with app WBPhoto Light Meter, running on Redmi 9 that i just got. I didn't have it in mind to measure the previous strip. On my good (-ish) eIPS monitor, it displays 6500 flat, which is a pretty good sign, and specced LEDs that i happen to have on hand shone right into the camera seem to produce vaguely reasonable values too, even with understanding that it cannot be ideal in presence of near-IR and near-UV emission, which phone cameras are slightly susceptible to.
The color temp is probably off on mine too, but I just use this monitor as a second to display datasheets so I'm not too bothered by it. The bigger issue imo is on max brightness the leds in this kit are noticeably dimmer than a ccfl.
@@sjm4306 I had the opposite experience, on a 22" the retrofit turned out extremely bright. It will easily be super bright on a 17".
The inputs on the board are a little on the weird side. Besides the possibility that you got a different version of the board, maybe you drive it such that you're not reaching full current capability. ENA input of the PCB is actually analogue and goes to the DIM input of DF6113 IC. If it doesn't reach 3.3V, it will dim down. DIM input of the PCB messes with the feedback instead, and might better off not be connected at all, it's just weird. Some signal conditioning may need to be applied, like driving ENA from the PWM of the OEM driver instead, potentially with a little one-transistor inversion circuit if need be. I forget how it worked out when i last performed the conversion. I don't really mind even plopping an ATTiny13 or a Digispark on there if i need it to be any more complex than that.
That's actually very possible, I cant remember what I ended up doing with the ena/dim inputs (is it weird I have to watch my own video to figure out what I did lol) but I remember I chained mine off the 22v rail from the power supply board so it's possibly it just cant supply enough current or ends up thermally throttling for the leds to be at full brightness.
Budget LEDs tend to have low CRI (color rendering index). Blueish tint means there are lack of red light coming out of luminophore. I suggest to find LED chips with CRI≥85.
Most cheap consumer white leds only have significant peaks in the blue and yellow parts of the spectrum to approximate white light (blue/violet directly from the led and yellow from the phosphor's emission due to excitation by the blue light). From my understanding high cri leds dope the phosphors to add other peak emissions beyond blue and yellow. I wonder if a better way to do this (albeit more costly and difficult) would be using rgbw leds and manual calibration.
Where can I get the LED driver board ?
The led driver board came with the led strip kit, but the extra board I used to drop the 22V lcd power supply to 12V to safely drive the driver is just a cheap dcdc buck converter module off ebay.
why did you need to install mini -360 board ? . hello :) . thanks
The internal lcd supply was ~24v iirc, but the led strip controller chip can only take 12v max so I had to use the buck converter to generate 12v from the 24v. Every monitor is different though, so if your has a 12v supply already then the buck converter isnt necessary.
@@sjm4306 gracias
wow..super..bro i broke my backlight strip of aoc monitor too..plz help..where can i fine backlight strip
I bought them off ebay, but I think amazon has them as well.
@@sjm4306 so u mean my oac monitor will fix this backlight strip that u used in this video bro
The exact process will be slightly different as your monitor will have a different power supply board inside, but generally the same kit I used can be used to fix your monitor.
@@sjm4306 thanks bro
If I don't have a pinout on the board, how do I know which pins are for the ENA and DIM?
You will have to follow the traces on connectors then and look up the datasheets for connected chips to figure out what pins to use. Unfortunately every lcd board is different so I cant tell you exactly how yours is wired.
@@sjm4306 Oh, I see. Thanks, appreciate the quick reply.
@@sjm4306 I can't seem to find a datasheet for the chip. Am I all out of luck or is there any way of finding it otherwise?
Sorry if it's not online it could be under NDA and the only company with access to it is the manufacturer. There's little you can do other than trying to reverse engineer the circuitry and carefully probe stuff.
@@sjm4306 Ah, allright. I did probe all the connections from the PSU to the main board for voltage, would 5v or 3v tell me anything useful? Sorry for all the questions, very new to this.
Thanks buddy 2019
No problem!
@@sjm4306 mine come in a pvc pipe and still was broken in half lol Go figure huh
Why buck inverter you use it ?
My monitor only has a 24v supply in it and the led constant current driver that came with the kit has a max input voltage of 16v, so it would fry instantly without the buck converter to generate a lower supply voltage. If your monitor has a 12-16v supply rail then you dont need the buck regulator.
WAO GREAT .......i found the solution
How would I figure out what pins to solder the cables to without having a legend of the pins right next to it?
You'll have to deduce it from connected capacitors/power planes, or if it's a signal pin then measure with a multimeter/oscilloscope to figure out what they do.
@@sjm4306 thank you for response. my board has 11 small pins to where the PSU connects to the smaller board. I have the black probe connected to the first pin, and the red probe going down the line. as i go down the line, pin 2 & 3 read 0V, pins 4,5,6 read 5.1V, pins 7,8 read 12V, pin 9 reads 3.2V, 10 reads 2.2V, and the 11th pin reads 0V. do these numbers mean anything ?
Of course they mean something. You'll need more info though to make sense of them. For example trace what the pins connect to. For example if you follow them to a chip you can look up the pinout and datasheet for that chip to find out what that pin does, and the voltage may tell you what state that pin needs to be in/etc.
@@sjm4306 ouuu didn't think of that, thank you. I'm pretty new to this so I have to figure everything out before I actually start fixing my monitor
sjm4306 also quick question, will i be able to get power from anywhere on the board? like from the legs of a capacitor?
What if I cracked one of the tubes is it dangerous ?
Just be careful of broken glass and there's a tiny bit of vaporized mercury inside but should be fine so long as you wash your hands after handling.
sjm4306 thank you because if was very scared (just have you ever broke one ? )
Yes I've accidentally broken ccfl tubes before
i have 2x caps POP , at home , becuase the reverse position :)
Oof sorry to hear that
Cool repair.
My Viewsonic 2038wm-LED monitor turns on but the screen image flashes every few seconds (screen is on, screen is off, screen is on. The image actually looks good, not faded or anything). The term may be it's flickering every second or every few seconds?
These are cylindrical electrolytical capacitors, I see which aren't bulging or seems to be damaged:
Electrolytical Capacitors
100v 33nF
25v 30nF
25v 330nF
10 680nF
50v 47nF
16v 470nF
16v 470nF
450v 100nF huge one (the largest)
Ceramic capacitors I see are:
4 blue ones, one blackish & one light brown
The nearest to the connector to the LCD controller board are the two 16v 470nF capacitors.
Which could be the possible culprit?
Thank you. God bless, Proverbs 31
Do you mean uF (nF is a tiny capacitance)? I would desolder and check them with an ESR meter (you can get cheap transistor testers with ESR measurement off eBay and Amazon) and replace the ones near the backlight dcdc circuitry if necessary as they are probably causing the flickering. Does the whole screen flicker or is it just a spot/corner? Does it take a few minutes to start flickering or does it happen immediately when turned on? It could also be a dying series LED is thermally oscillating.
@@sjm4306 Hi. Thanks. I meant nF:-)
The monitor turns on and the image is bright and ok but after a few seconds, it turns off, then a few seconds it turns on. That turning off then on, isn't fast like in normal flickering.
I wonder if that is the main capacitor, the biggest one or it's one of the smaller ones near the connector of the LCD controller?
I only got to buy these electrolytic capacitors (the store didn't have the big electrolytic and didn't have one of the smaller ones).
These are the electrolytic capacitors on this LCD monitor's PSU:
100v 33nF
25v 30nF
25v 330nF
10 680nF
50v 47nF
16v 470nF
16v 470nF
450v 100nF
Which capacitor should I change first? The nearest to the LCD controller connector are the two 16v 470nF ones.
Thanks again, in advance. Amazing work on your all transparent AGS-101. I wish I had that case (it seems rare).
It would be the large dc link cap otherwise the entire monitor wouldn't work. I would start with the ones near the backlight dcdc as those are directly responsible for stabilizing the LED drive current.
@@sjm4306 By the way, if the fuse does not have legs on them, how thick should the copper wire be (for its "legs" to solder to the board) for 1.5A, how about for a 18A (250v)? Thanks again.
By the way, if my different video game consoles and one more gadget (all are 100v except for three 110v US) have a total of 198w, how many wattage should the step down transformer be, if I switch all those consoles on at the same time (all are plugged in w/ two surge protectors)?
Thank you.
nice, if a monitor dies on me i know what i should try :D
You have led driver. Not need mini step down regulator.
Absolutely necessary in my case, my monitor only has a 22v rail from the internal supply and the constant current chip in the driver has a max input voltage well below that (I think it was around 16v when I last checked the datasheet). If I wired it straight up it'd likely blow the first time I powered it up. Now another monitor may have a lower voltage available like 12v or 15v in which case you'd be correct, but that was not what my monitor had.
@@sjm4306 OK. Understood.
Grobmotoriker OMFG
Hi Sjm4306 👋
Hi!
Your videos are helpful, thanks Sjm4306👍
You're welcome, I'm glad you like them.
Do u know how much it costs to send a package with fragille warning.? For 4 bucks u wanted what? Smh
When I buy something I hold the seller accountable to what was promised regardless of the cost/value of the item. In this case the listing was for unbroken led boards, it's their problem if they set their margins too low and had to severely cut corners on shipping packaging.
Opening music is so horrible it gave me a headache
... you know you can quickly skip ahead by using the right arrow buttons on a computer or by double tapping the right side on android/ios right? If you have a headache, you only have yourself to blame by sitting through something that gives you a headache.