How to connect a 7 inch matrix to a laptop. How I made a second monitor from a laptop display
It so happened that I ended up with a dead HP 625 laptop with a 15.6” matrix and an NTA92C VGA/DVI LCD panel controller in my hands. I had no desire to spend money on restoring the laptop, so it was decided to make a second monitor from the above parts, so that with VESA mount for a regular monitor. With minimal time and financial costs for me as part of a “weekend project”.
A “weekend project” is something I do for a short period of time (weekends or for 1-2 weeks) in order to solve problems that are atypical for me. Main goals: solve a problem, gain experience and skills, expand your “toolkit”.The ability to connect laptop displays to a computer (VGA/DVI/HDMI) is provided by various types of LCD panel controllers. The NTA92C controller was suitable for my display (you can buy it on ebay, aliexpress, etc.)
Source materials
- Display 15.6"
- NTA92C controller
- Power supply for controller 12V 4A
- Metal profile for plasterboard 60x27
- Metal profile for drywall 28x27
Tools
- Drill
- Riveter
- Tapping tap
- Metal scissors
- Assorted pliers and screwdrivers
- Glue gun
Theoretical part
The display will be attached to the monitor in place for a VESA mount and stick out from the side like an ear. It weighs quite a bit, which means the monitor will skew. To avoid distortion, you need to add a counterweight on the other side.After weighing and measuring everything, this is what I got:
42cm * 920gram + 28cm * 210gram = 24cm * Xgram
X= 42cm * 920gram + 28cm * 210gram / 24cm = 1855 gram
This is the figure I was guided by when assembling the counterweight. I took coins from scrap materials for counterweight.
Practical part
Display
The display from the laptop was removed along with the case and hinges (it seems to be more aesthetically pleasing). There is a limiter on the hinges for opening the laptop lid and it really bothers us, since now they will be open at angles greater than 140 degrees.The limiter is a protrusion in the frame. You can either grind it off or hammer it back in, which is what I did.
Next, having made a housing for the LCD controller from the housing from the power adapter (yes, I disassembled the power adapter), I attached the whole thing to the back of the display with a glue gun. This was the end of the display.
Frame
We assemble a square from a 28x27 profile. This is necessary firstly because the display hinges and the 60x27 profile are attached to opposite sides of the square. And secondly, to increase the thickness of the metal for the threads for the bolts. The profiles are fastened together into a square using a riveter, then threads are cut for the bolts.
In the 60x27 profile we make 2 holes for a VESA mount (I have it VESA MIS-D, 100, C - that is, the holes are 10 cm apart) and fasten it with rivets to a previously made square.
power unit
![](https://i1.wp.com/habrastorage.org/getpro/habr/post_images/e17/f10/7ab/e17f107ab6c6f7e2e14a9110ceae448b.jpg)
The power supply case was disassembled for subsequent placement of the power supply inside the 60x27 profile (it did not fit with the case)
I made a replacement body (as insulation) from cardboard and glued it to the profile with a gun. The power supply itself is glued at the corners to the cardboard.
As a result, I got this “shovel”.
Installation and connection
We fasten the “shovel” to the main monitor with bolts (left over from some furniture) on VESA. We attach a counterweight. Connect DVI and power.
The display was not immediately detected. Let's go here: Control Panel → Display → Screen Resolution Settings → Find and customize it to suit your needs. All! Our second monitor is ready!
Flaws
- Not good good matrix. Firstly, it is glossy and because of this it glares. Secondly, not very good angles review (Thankfully, the hinges have not lost their ability to rotate the display to the desired angle).
- Due to the difference in aspect ratio of the displays (the main one is 1920x1080, the second one is 768x1360), there is no effect of a single display. Yes, I made the resolution 768x1024 - much better with solidity, but I was not satisfied with the quality of the picture (the letters floated a little).
- My profile design is not very good because... it has poor resistance to torsion, which arises due to its characteristics and the way loads are applied to it. This problem can be avoided by fitting a second profile to the bottom two holes. VESA mounts and riveting everything into a rigid structure.
By the way: I don’t know whose fault this is, but when I connect my display to the VGA output Samsung laptop R519 under Xubuntu the colors on the display were very strange.
Conclusions
Another “project” has been completed and the final result has been obtained.The total cost of the design with the price of a matrix of 1000~1500, a controller of ~900 rubles, a power supply with a cord of ~400 rubles and consumables of 50~100 rubles is 1950~2500 rubles. For this money (well, maybe adding a little) you can buy a completely sane second monitor. I got a second display for practically nothing (after spending only 25 rubles on a small drill and 150~200 rubles worth of coins). I had everything else one way or another. It was only necessary to rummage through the drawers of the desk.
If I had to do it a second time, I would use aluminum corners or squares.
Many of you have old or broken laptops that are lying around, but some of the spare parts in them are quite working, so it’s a shame to throw away the device. And if you suddenly want to make a second or third additional monitor for your computer, then this laptop will come in handy. Today I will tell you how to make a monitor from a working laptop matrix that can be used everywhere.
The first thing we need is a working laptop matrix. At this point, you must be 100% sure that it really works, otherwise the following steps are useless. So my patient - HP Pavilion dv9000, in which one of the display mounts is broken and the video module burned out, but the 17-inch matrix with a resolution of 1440x900 is working.
We carefully disassemble the laptop and remove the display, and then the matrix itself. For most devices on the network there is detailed instructions for disassembly. I also removed the speaker and webcam. As a result, we get approximately the following picture.
1) Jack for connecting LVDS cable.
2) A plug that connects to the backlight inverter.
We look carefully at the stickers and find the matrix model. As you can see, I have a laptop HP, and the matrix is from SAMSUNG, we are interested in the inscription LTN170X2-L02, this is the matrix model. The fact that after the “-” sign can be ignored when searching, only the marking is important to us LTN170X2.
If you don’t need any video inputs, then you can easily find, for example, a board with one of the inputs you are interested in. This way you can also reduce the cost of the device.
1) Input for connecting 12V power
2) HDMI input
3) DVI input
4) VGA input
5) Audio input
6) Audio output
The following components are included in the kit (they may vary slightly appearance and connection methods):
1) LVDS cable that connects directly to the monitor matrix.
2) An inverter responsible for the operation of the backlight.
3) Main board with controller.
4) Push-button interface for adjusting image parameters.
5) Cable for connecting the push-button interface.
6) Cable for connecting the backlight inverter.
There shouldn’t be any problems with the connection; you won’t be able to mix up the wires either. When assembled, everything looks something like this:
Next, we should check whether our device works at all. We connect the LVDS cable to the socket in the matrix, there is also a cable for backlighting on the matrix, we connect it to the free socket of the backlight inverter. We find it in the bins or buy a 12V power supply, perhaps one from your broken laptop will do. Be sure to check that the plug fits easily into the control board socket. Then we connect the video output of the computer to the video input of the control board with one of three cables (HDMI, DVI, VGA). We supply 12V by plugging our power supply into an outlet. Oops! Nothing happens. Like a regular monitor, the device has an on/off button. Press the button "ON\OFF" on a push-button interface. And lo and behold! We see the image. If you still have a black screen at this stage, check whether you have connected all the wires correctly, whether they fit well in the board sockets, and whether your power supply is working at all. I got it right the first time.
Next, this whole bunch of wires and boards needs to be beautifully mounted on the monitor. I screwed all the boards to the back plastic wall of the monitor, after drilling two holes for the LVDS cable and the backlight inverter cable, since they connect directly to the matrix. I also screwed two metal corners to the back wall so that I could easily place the monitor on the table. You can attach mounts to mount the monitor on the wall if necessary. This is what happened in the end, my brutal monitor =)
Where and how you can use this monitor:
The first two points only apply to video cards with multiple video outputs.
1) As an additional desktop. For example, you start a movie on one screen, and on the second you surf the net or type text. And there is no need to open\close, minimize\maximize interfering windows.
2) As a backup monitor. You can take him to another room and watch, for example, a movie or your favorite show there. My board has an audio input and output, so you can connect acoustics without any problems. It will also not be a problem to find a long video cable; I worked with a VGA cable, which was more than 20 meters long.
3) If you are familiar with Raspberry Pi, then you can also connect this monitor to it without any problems.
P.S. I will answer all your questions in the comments.
Good day! Today I will tell you how, with the help of one parcel from China and the trash that is lying around your house make a TV, or at least monitor. The fact is that many probably still have ancient laptops lying around, some damaged monitors, non-working tablets and all this can be put to use. Well, yes, you cannot connect the matrix separately, but with the help of a simple device, namely universal scaler, Can connect any matrix to HDMI,VGA or even make a TV.
And so what we have.
I ordered myself a rather advanced scaler.
And I came across this tablet, it’s still alive, although the sensor is already broken, the battery doesn’t hold up so well, it’s all scratched, but you can borrow the matrix from it.
We disassemble the tablet to gain access to the matrix.
We turn off all the cables and throw everything aside except the matrix.
The matrices have quite standard connection , in them LVDS interface And standardized range of connectors. You can see which connector your matrix has by its appearance or by datasheet. There is a separate cable for each type of matrix. For example, I have several loops.
1 is an older standard, where matrices were still lamp-illuminated.
2 is a newer standard, where LED matrices go.
3 - these connectors are found in 7-inch tablets and various small ones.
On the other hand, the connectors are more or less standardized and fit into almost any universal scaler.
I have never used such a scaler before in this much more features compared to the ones I used, even remote control included.
Before connecting the matrix it is necessary configure the board correctly(scaler) so as not to spoil the matrix. I definitely recommend downloading the datasheet for the matrix first, so that you know what the matrix resolution is, what the logic and backlight power supply is.
The first place to start is to look from left to right. There are a number of jumpers on the scaler, the top left one configures logic voltage, it must be selected based on your matrix. As a rule, laptop matrices have a power supply of 3.3 volts, in regular monitors 5 volts, but there is also a 12 volt jumper here, to be honest, I don’t know where this voltage is used. We immediately change this jumper so as not to burn our matrix, in my case the logic is 3.3 volts.
The next set of jumpers takes longer to set the screen resolution. I would like to note that in addition to the screen resolution, the bit depth also changes. On the back of the scaler there is a cheat sheet that says resolution and bit depth. The bit depth can be 6-bit and 8-bit; visually, 6- and 8-bit connectors differ in the number of contacts. You can again read the information about the bit depth of your matrix in the datasheet.
Before moving on to the matrix, you need to study the datasheet; it is very easy to find by looking at the sticker located on the back of the matrix. In my case it's " LP101WX1" In the datasheet for the matrix, we are interested in 3 or 4 points, depending on whether it is an LED matrix or a matrix with a cold cathode lamp. First of all, let’s determine what resolution the matrix is, just flip through the datasheet and look for this entry. Here in our table it is indicated pixel format(Pixel Fotmat) that is, it is 1280x800, respectively, you must select this resolution using the jumpers on the sayler. Interface width corresponds to the number of colors in in this case This 6-bit or 262,144 colors. These two parameters are enough for us to select the correct mode of operation of the matrix.
But in order for the matrix to survive, we still need set the correct voltage, let's scroll further. And here we have pivot table electrical characteristics. Logic, that is, logic power supply, logic supply voltage ( Power Supply Input Voltage) from 3.0 to 3.6 volts, typical 3.3 volts, accordingly we set the matrix power jumper to 3.3 volts.
And just in case, look at the backlight, this item should only be looked at if the matrix is with LED backlight. As it is written on the board, the board is powered by 12 volts, and our backlight works from 5 to 21 volts, 12 will be just right. I haven’t seen any other matrices that have a supply voltage of 5 volts, but I assume that this could happen if you use a matrix from any small tablet. Therefore, be sure to look at this parameter, otherwise you may simply ruin the matrix backlight. If the power supply is different from 12 volts, then you cannot directly connect the backlight power connector; you will need to provide the required supply voltage.
And so, we set up the scaler in accordance with the data from the datasheet. I'm interested in 1280x800 and 6-bit resolution, for this I set jumpers F and G
The jumpers have been configured, now let's go through the elements on the board.
1 - the first two connectors are power
2 - serial port
3 - DC-DC converter
4 - linear stabilizer
5 - connectors (VGA, HDMI, RCA, audio and high-frequency antenna connection)
6 - backlight control
7 - buttons and all controls
8 - LVDS connector where the matrix is connected
9 - memory
10 - processor
11 - power amplifier
12 - TV tuner
More information about connectors
Backlight control connector.
If you have LED matrix, that is, LED, then you don’t need to bother, it’s right in your matrix backlight control controller installed and this connector goes directly into the cable. Those. Just connect the matrix and you don’t need to worry about anything else.
If the matrix is ancient CCFL lamps, this can be determined by the additional wires coming out of the matrix.
Such lamps can be installed in the matrix and wires come out of it. In laptops there is usually 1 wire, in a monitor matrix there are 2 or 4. To connect such a matrix you can use universal inverter for lighting. It comes in 1, 2 and 4 outputs, i.e. each output is the connection of one lamp. The inverter must be selected according to the number of lamps in your matrix, that is, you cannot connect only 2 lamps to an inverter with 4 outputs, since the inverter will go into protection, because all outputs must be evenly loaded. Therefore, if the matrix is for 2 lamps, we buy an inverter for 2 outputs, if for 1 lamp, we buy for 1 output. The connectors are unified so they fit 1 in 1, they just plug in like that and that’s it.
Let's start connecting
For this we need a cable, it is easy to plug in, the jumpers on the board are already configured. LVDS aligned to the first leg, on the cable this is a marking in the form of a spot of paint, and on the board the triangle is the first leg.
Just in case, we check whether the backlight is suitable. Red is plus, black is minus and the only wire is to turn on the backlight. We turn the board over to reverse side and compare the inscriptions near the contacts with the wires, if everything matches, we connect.
We also need some kind of management. By the way, more details about the control, the block where I connected the IR receiver is the control. Here are the buttons, they are all labeled, the buttons can be purchased separately or you can connect your own.
In principle, that's all, everything that needs to be connected.
Turn the matrix over and connect the power. If you are going to connect to a computer, then you can take power from the computer's power supply. Turn on...
Now you need to deal with the remote control to find the menu and change the language. I think this process is not worth describing, since everything may be different for your scaler. Unfortunately, I only found English in my country, but it doesn’t matter, I’ll use it. And on the same settings tab, I found the menu size and increased it so that everything was better visible.
Well, let's try connecting the camera via HDMI. In general, when I connected the camera, it turned out that the halftones of the colors were displayed incorrectly.
At first I thought that the reference voltage buffer in the matrix had burned out, but after connecting the matrix to the tablet I realized that everything was fine with the matrix, it had not burned out. Having rummaged around the Internet, I found service menu. It turns out that you need to change the way the scaler works with the matrix in the service menu. To do this, go to the menu and dial code 8896, and the service menu opens to us. In the menu we find system settings(System setting) -> Panel settings (Panel setting) -> and simply change color scheme(Color set). Going through all the options, we find the most optimal one, for me it was 3. Other scaler models may have a different access code to the service menu and a slightly different path to the color scheme settings.
Laptops break down and become obsolete, but some components in them remain working and can still serve. If the laptop screen is working properly, you can take it out of the case and turn it into a monitor. How to do this?
Disconnect the laptop from the power supply and remove the battery (if it is external and not installed inside the case).
Disassemble the body. Opening different models Laptops are carried out differently, but in general there is nothing complicated about it: you need to unscrew all the bolts (including those hidden, for example, behind the DVB drive) and carefully open the cover. Then remove the elements that prevent you from removing the panel and unscrew its fastenings. Do not touch boards, microcircuits or wires under any circumstances. Static electricity can damage components that are still working and may be useful.
Connect the matrix to a universal LDC controller - for example, LA.MV29.P or its equivalent. It can be bought in online stores (AliExpress, Banggood, etc.)
This controller is powered by a 12-volt adapter and supports almost all LCD models. The image can be sent to the controller from a computer, laptop or tablet via HDMI port, VGA or AV, supported resolution - up to 1920x1200 pixels. In addition, this board can serve as a TV tuner and display TV channels on the screen. Remote control included remote control and an infrared sensor.
Before placing an order, you should tell the seller the model of your matrix so that they can select a controller that is guaranteed to suit you. Important point: you must find out what voltage the matrix operates with, this will be required for the correct pinout of the cable. Look at the model on the back of the matrix, go to datasheet4u, find that model and look at its characteristics. Move the jumper on the universal controller to the appropriate position: 3.3, 5 or 12 volts. Be extremely careful: if you bet more high voltage than required, the matrix controller may burn out.
The controller will need to be flashed. To do this, copy the file lamv29.bin from this archive to the root of the flash drive, insert it into the USB port of the turned on controller, wait a minute, turn off the power, disconnect the flash drive, turn on the controller again and check if the matrix is working correctly. In the menu you can change the language from Chinese to Russian.
To configure automatic switching on matrix when power is applied, go to settings and enter 1147 on the remote control. The service menu will open. Go to the Advanced Setting sub-item and switch the AC on Mode option to On mode.
The controller can be hidden in some case or simply glued to back matrices. You can use a laptop or monitor case as a housing for the matrix. Of course, you can leave it as it is, although such a design will not look very aesthetically pleasing. If you use a matrix without a housing, it can be installed in a tablet holder with the ability to adjust the tilt angle.
Today we will conduct a small experiment in which we will find out whether motherboard laptop to display an image on a matrix of different diagonals.
The experiment will involve Westron JE70-DN boards.
The native matrix for this board is a 17.3-inch matrix model N17306-L02 Rev.C3.
We have this laptop after an impact and after repairing the motherboard.
After displaying the image on the matrix, it turned out that it had color distortions.
That is, if you withdraw white background, the color appears with a greenish-bluish tint.
To understand what the problem is, whether the problem itself is graphics chip in the cable or matrix itself, the simplest thing you can do is to connect another matrix.
We didn’t have a matrix of such a diagonal at hand, so we will connect a standard 15.6-inch diagonal matrix.
I have already tried this operation and we have an image.
As it turned out, the culprit is the matrix itself and the fact is that some of the red pixels do not work on it.
If we display a white background on the matrix, we alternately have stripes of green-red pixels.
Some red pixels work, some don't.
Therefore, the white background comes out with a greenish-bluish tint, this is due to the mechanical effect on the matrix itself, and there is nothing that can be done about it.
We connect the matrix to the laptop and see that the white inscription gives off a greenish tint.
It was a 17.3-inch matrix.
Now let's connect the test matrix; it has defects, but it displays an image.
This is model B156XW02V6.
As we see, here white distorted, without any color distortion.
Now we connect a 10.1-inch diagonal matrix from a netbook.
Let's see if it works on this platform.
It is also broken, but it displays an image.
As you can see, even such a small diagonal works without problems for us.
White color, as in the previous matrix, without distortion.
Watch the video below: