The principle of operation and features of the LED lamp
Thanks to the design of the 220 volt LED lamp, it consumes significantly less energy than an incandescent lamp and will last several times longer. Upon purchase, you can get a guarantee for the LED lamp, so do not rush to throw out the receipt and packaging.
The LED light bulb is designed so that the voltage at the output is reduced to the required values using the driver. Usually they do not exceed 2-4 Volts. The only drawback of these devices is the price. But the cost of the lamp pays off due to the service life.
The principle of operation of LED lamps
Despite the different appearance of LED lamps, they have a common principle of operation. The current is supplied through diodes, the number of which varies depending on the power of the lighting device. The color spectrum is set by a special composition that covers each crystal.
An LED lamp is a semiconductor element that converts current into light. For the required indicators of dissipation and protection of diodes, a special bulb is made (protective diffusing glass). Externally, the product resembles an ordinary incandescent lamp.
What LEDs are used
One of the main elements that is part of the LED lamp is a diode. They call it a semiconductor crystal, consisting of several layers. It is he who serves to transform the electricity supplied to the lamp into light. A diode is produced on the basis of a chip - a crystal with a platform to which the conductors are connected.
We advise you to watch the video: Explanation of LED lamps, disassembly of the LED lamp, the principle of operation.
To obtain a white glow, the chip must be coated with a yellow phosphor. When blue and yellow are mixed, white is formed. There are 4 types of LEDs:
- COB. With this production technology, the chip is mounted on a board. The contact receives reliable protection against oxidation and excessive heating. It also has a positive effect on the characteristics of the glow. If such a chip fails, the circuit cannot be repaired. This is the only drawback of the technology;
- DIP. The circuit consists of a crystal, two attached conductors, the lens is located on top. Such lighting devices are in most cases used as backlights on billboards and light decorations;
- Diode smd. Mounted on flat surfaces, which allows you to make devices of different shapes. It features improved heat dissipation characteristics. Such lamps can be used for any light source;
- "Piranha". The design is similar to the DIP circuit.But there are 4 outputs here, which improves the removal of generated heat and makes the technology more reliable. Piranha has become widespread in the automotive industry.
How are these lamps
The composition of the classic LED light bulb contains:
- plinth and supporting body;
- power unit;
- diffuser lens made of plastic;
- driver;
- chips;
- radiator for heat dissipation;
- printed circuit board.
The shape can be standard, that is, rounded or cylindrical. For a general use system, it is recommended to choose luminaires whose color temperature is at the level of 2700 K, 3500 K. Any values are allowed in the spectrum gradation. Such products are often used to emphasize interior elements or by advertising agencies to highlight the banner.
LED driver circuit
The figure below shows a simplified diagram of the driver used in 220 V lamps.
The scheme involves the use of only basic parts. There are 2 resistors here - R1 and R2. Diodes HL1 and HL2 are connected to them according to the anti-parallel principle. Such a device provides the circuit with reverse voltage surge protection. When turned on, the signal to the lamp rises to 100 Hz. Voltage 220 V is supplied through C1 (limiting capacitor). From here it enters the rectifier bridge and chips.
Assembly types
There are 2 main types of assembly of LED lamps for 220 volts:
- with diode bridge. The circuit includes 4 diodes. The bridge transforms the incoming current into a pulsating one. Passing through the chips, the sine waves change, which provokes a loss of polarity.During the assembly process, a capacitor must be connected to the output in front of the bridge. Before the terminal (negative) - a resistance of 100 ohms. To smooth out possible drops, another capacitor is mounted behind the bridge;
- with resistor. Assembly is available even to inexperienced craftsmen. For work, 2 resistors should be prepared, as well as chains with the same number of chips installed in series, taking into account the polarity. From the side of the first resistor, the strip is connected by the cathode, the second - by the anode. The lamp will have a soft light due to the switching on of the chips in turn. Such devices are often used as table lamps.
A video will also be useful: Kit for assembling an LED lamp. We collect on our own.
Structure Assembly Diagram
How the LED lamp will work directly depends on the manufacturer and the price of the product. Differences can be seen if you remove the diffuser. First of all, you should pay attention to the quality of soldering chips, as well as connecting wires. Cheap light bulbs last less than high-quality and expensive ones.
low quality chinese light bulbs
When purchasing a light bulb for no more than $ 3, you should not count on the symmetrical arrangement of the LEDs on the board. This suggests that the soldering was done manually and in haste, and the wires were selected with a minimum cross section. There will also be no reliable driver here. Instead, a transformerless circuit with a rectifier and a capacitor is implemented.
When you turn on a cheap Chinese lamp, the voltage will first decrease with a metal-film capacitor (non-polar), straighten out, and then increase to the desired values. The current will be limited by the standard SMD resistor. It is installed on the printed circuit board along with the chips.
If you have to diagnose and after repairing lamps of this type, you should definitely follow special safety precautions. Each element, which is a component of one circuit, may be under voltage, dangerous to humans. If you accidentally touch one of the live parts, you can get an electric shock. The same thing can happen if the multimeter probe accidentally slips and causes a short circuit.
Branded LED lamps
Expensive and high-quality light bulbs have a pleasant appearance, but these are far from all the advantages. The quality of the element base will be much higher than that of the Chinese counterpart, purchased at a low price. The installed driver has a complex device. One of the ways to assemble it involves installing a pulse transformer, as well as a current converter, which further stabilizes the resulting load.
The transformer may not be installed. The main load will be directed to the microcircuit that stabilizes the input voltage, which:
- has a negative feedback system;
- the possibility of dimming;
- maintains a current with a given pulse width.
Choosing a high-quality 220 V LED bulb with a current driver, the buyer receives a device protected from interference and surges in the network that meets the specifications specified in the passport. The radiator installed here will provide a quick heat dissipation. This light bulb will last more than 5 times longer than a cheap Chinese one.
Tips for choosing and connecting
When choosing an LED light bulb, it is worth considering not only the power, but also the generated luminous flux.Specifications can be found on the packaging. For example, a 60 W lamp emits a flux of 800 Lm, and a 100 W lamp emits 1600 Lm. It is also recommended to consider the following:
- lighting color. Before buying, decide which lamp you need, with a warm or cold shade. An incandescent bulb has characteristics of 2700-2800 K (warm tones). The glow with indicators of 4000 K is white. For the home, it is recommended to select warm colors, as they will emphasize home comfort;
- switching on and off frequency. Frequent switching on may affect the life of the bulb. It may burn out due to poor-quality electronic circuitry. The LED lamp should not be installed in rooms in which the light will often turn on and off. For example, if you need a light bulb for a bathroom, you should buy an expensive model, since a cheap analogue will burn out quickly enough;
- dimmer compatible. A dimmer is a light intensity regulator. Not all lamps are compatible with this device.
Before buying a light bulb, it must be carefully examined and checked for visible defects. Pay attention not to the radiator, it should not be type-setting. This affects the service life of the product. If it will be covered with thermoplastic, this is the best option. When turned on, the lamp should not flicker. If it is invisible to the eye, it should be looked at through the camera of the phone. A flickering light bulb is not worth buying.
