LCD TV replaced CRT - picture tube relatively recently. Functional, low power consumption, and no harmful radiation, such LED and LCD matrices have become popular among electronic devices and have almost replaced the outdated devices that use CRTs. However, new items also break. Various malfunctions of TVs are not uncommon, including breakdowns of LCD matrices. In this connection, their replacement or timely repair is required. Replacement or repair of the LCD matrix can be done by hand.
The principle of operation of the lcd matrix
An LCD matrix is a glass working surface with several million pixels; they change color, as well as their brightness, due to the influence of external control signals. Matrix pixels form the image that we see.
Chips are used to control some of the pixels. Microcircuits are called drivers that control signals that send a specific signal for each pixel. Typically, the control drivers are located on flexible stubs soldered into the very base of the matrix glass. This loop cannot be separated from the glass, and one loop cannot be replaced either. In addition, it contains power supply parts for the drivers, as well as decoder chips.
See also - How to fix a TV with your own hands
Matrix faults
Breakdowns of the matrix can be conditionally divided into the following groups:
- Mechanical disturbances (matrix bending, water penetration, impact).
- Breakage of microcircuits and other parts (resistor, diodes, capacitor, inductance), ensuring the continuous operation of these microcircuits that form the image. They are located on a flexible non-removable cable.
- Non-removable loop violation
- "Burnout" of pixels that have ceased to be efficient without mechanical justification.
- Backlight does not work
The malfunctions of the matrices described above lead to their replacement, since the repair will be too expensive or simply impossible. Replacement in this case is a priority option. For example, a backlight inverter for fluorescent lamps is often located on the power supply board, and the lamps are also easy to replace. It is more difficult to malfunction LED backlights, usually the manufacturer makes control of it on flexible non-crease cables. However, here you can try to make repairs yourself.
Dismantling a TV with a front housing system
The principle of replacing the matrix depends on the TV model, manufacturer, and also the size of the matrix. However, there are general rules. There are two popular types of housing fastening - screw connections and plastic latches.
The front panel of the cladding must be squeezed out and the latches removed. Then you will see the matrix screwed to the main body of the TV with metal screws or screws. It is necessary to unscrew each fastener and separate it. Be careful - perhaps the screws are duplicated with latches.It will also be necessary to dismantle the bolts on the back of the TV, they fasten the case with a metal screen that protects the power supply from faults, as well as the control board.
When everything is done properly, the matrix with all the electronics should be detached from the case. In order to prevent chips and scratches, it is recommended to place the element on a soft cloth, flannel is perfect for this. Next, we disconnect the panel from the connecting cable, be extremely careful. In some situations, for additional fastening, as well as protection against slipping of the loop, the manufacturer glues a strip of adhesive tape to the connection.
Carefully remove it, lift up the pawl clip located on the connector, for this you can take a small tweezers. To avoid damaging the narrow paths, you must try to get the train without swinging it in different directions. Then you need to remove the stiffening panel from the matrix. For this purpose, we unscrew the screws from the ends, from different manufacturers they can be in the amount of 2 - 12 pieces on one side.
Dismantling the matrix with rear disassembly
This repair has a similar order, except that there is no front facing television frame, but this is partly the case, since there are quite a few models, therefore there are certain technological subtleties. In the future, the analysis of the control board, as well as the base of the matrix rigidity, is identical. Installation of the matrix is carried out in the reverse order.
When performing these operations, you can make a hint. If you first decided to replace the matrix with your own hands, then it is recommended to record the actions using a camera. On this, in principle, everything. Remember and follow safety precautions, and follow each step carefully when repairing or replacing plasma or LCD TVs.
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