Drivers for LEDs: types, operating principles, models, prices

LED-lighting economize on energy, it is a compact, bright and very effective. However, the cost of LED strips and spotlights is quite high and in order to obtain significant economic benefit needs as much as possible a long period of operation. To ensure the longevity of these devices is necessary to organize proper power supply, under the responsibility of drivers for LEDs.

What is a driver for LEDs - why do they need?

The main feature that is designed to perform driver LED lamp - a AC conversion (220) a standard household network into direct current voltage with predetermined parameters. The value of these parameters should exactly match the requirements specified in the illumination device ID. This will provide a uniform and stable glow LEDs, and to prevent premature degradation of the semiconductor crystal.

Historical note: the first time the effect of the EL luminescence of semiconductors was discovered in 1907 by British physicist Henry rounds. Then again, independent discovery in 1927 by the Soviet physicist O. Losev B., who has realized the practical value of this discovery, and received a patent for "Light switch". However, practical application LEDs as a source of light for the first time achieved Holonyak Nick in 1962. Mass LED lights in red and red-orange tones began to be issued only in 1976 company General Electric.

Depending on the voltage conversion distinguish the following types of drivers:

• for domestic use, lighting, office and industrial premises used LED-lighting with LED driver circuit for 220 V;
• a handheld portable lamps, automobile, motorcycle and bicycle headlamps are used DC current from the power supply 9 ÷ 36;
• some models of low power light-emitting diodes may be connected in a network of 220 V without the driver, but in this case, wiring diagram resistor must be present.

Scope drivers for LEDs

Drivers for LED strip and LED-lamps are used everywhere:

• Street lights;
• Residential and industrial premises, offices;
• LED Strip additional technical backlight and holiday illumination;
• compact portable devices large light power;
• transport.

LED-lamps should be used everywhere where a longer period backlight artificial lighting.

The principle of operation of the LED driver

The operating principle of the driver, and its main difference from the stabilizing power supply is to maintain the predetermined range of current parameters, regardless of the magnitude of the output voltage.

As can be seen from the diagram, the current stabilized R1-R4 resistance. It receives a predetermined frequency passing through the capacitors C1 to C2. A diode bridge is used for rectification. It should be noted that the stabilization of the frequency and voltage rectification is carried out both before and after conversion from AC to DC. Thus, maximum accuracy is achieved given parameters.

The main characteristics of drivers

The main features that are necessary to pay attention to the purchase of ice-drivers LED lamps, relate:

• Output voltage. The value of this parameter depends on the number of LEDs in the lamp power supply method as well as the magnitude of the voltage drop across the LEDs.
• Rated current. Its size should be sufficient to LED source provides optimum brightness. It represents the total amount of power consumed by each LED.
• Power. The value of this parameter affects not only the total power of all light-emitting diodes LED-device, but also the color of light. It is strongly recommended to purchase device that can provide the required power margin of at least 25 ÷ 30%.

In addition, it is imperative to take into account the color of the LED. Depending on the color characteristics of the semiconductor chips even when passing electricity at the same current intensity, the voltage drop component can vary substantially:

How to choose a driver for LEDs

When the driver for the acquisition of LED strip and lamps We need to pay attention primarily on the output voltage. The vast majority of devices, it is indicated as a range. On the market a variety of devices implemented with a working output voltage of the interval 2 to fifty or more.

For example, if it is necessary to receive the light source of the three series-connected white LEDs with capacity of 1 W each, it is necessary to take a driver performance U - 9 ÷ 12 V, I - 350 mA. The voltage drop for the white crystals amounts to approximately 3.3 V. Hence a series connection of these values ​​are summed up and 9.9 V, which completely satisfies the parameters of the working range of the LED driver.

Practical advice! For LED lamps of 10 W it is expedient to use pulsed driver, preferably assembled on a chip UCC28810.

Term driver service

One of the most important indicators of the quality of LED-driver whether working life. In high-quality devices it is not less than 70,000 hours, the company manufacturers provide a guarantee of not less than five years. The average quality of the resource driver is not more than 50 000 hours. Upon acquisition must necessarily perform by matching the nominal output parameters declared. The guarantee must be at least a year. The device of questionable Chinese manufacturers have a service life up to 20 000 hours. As a rule, they are not guarantees and certificates confirming that the device is adapted for operation in the harsh Russian climate (this is especially important for light sources used in street).

Especially Chinese drivers

The modern market offers a wide range of drivers for LED-lamps from different manufacturers. Most of them are produced in China. They are an affordable cost with the declared quite high performance. However, in most cases, their real figures do not coincide with those in the specification. For example, when the respective characteristics 50W device will operate only on said short-term power. Thereafter index might fall to 40 watts or 30 watts. Also in the circuit may be omitted and the capacitors resistance situated after the diode bridge. This will not only reduce the quality of lighting (visit will dim may flicker), but also significantly reduce the life of the LEDs.

How to check the driver for the LEDs on the performance and conform to the parameters of power can be found in the video:

Check matrix LED-spotlight:

Types of drivers by device type

There are two types of drivers for LEDs:

• Linear. Typical linear driver circuit LED lamps It is based on a transistor with P-channel. Such a device is better used if the input voltage is unstable. It provides a smooth stabilization current, reliable in operation and has a reasonable price. Despite such advantages are not the driver is not widely used. It is characterized by low efficiency in the process releases a lot of heat and can not be used to connect powerful LED bulbs.

• Pulse. The principle of operation is based on pulse-width modulation. current conversion efficiency of devices such as high as 95%. They have a small size, emit little heat, protect LEDs from the negative impact of external factors. Their use has a positive effect on the duration of the operation of LED-lighting.

Important! Pulse drivers have a sufficiently high level of electromagnetic interference. In theory, people with pacemakers may experience discomfort from being indoors, lit by such devices. However, as practice has shown that with the pacemaker affect the magnetic field of the driver is necessary to find a person at a distance of less than a meter from the high power LED-spotlight.

Dimmable LED drivers

The structure of modern drivers for LEDs in most cases consists of devices that regulate the brightness of the lighting. application dimmable device It allows you to set a comfortable level of lighting in the room. In addition, it saves working life LED-lighting.

Dimming device may be between the power supply and the LED-illuminator. These devices control the energy supplied directly to the LEDs. Typically, this impulse devices based on the PWM control. They regulate the magnitude of current flowing. In some cases, negative effects such as flicker may occur when using LED-budgetary sources.

The second type of dimmer power converters performs control. In principle, their effect is both PWM control and controls the current flowing through the device. It may be observed not only change the brightness but also the color of the LEDs. For example, white LEDs with such adjustment can emit yellow light at lower intensity and bright blue exaggeration.

Driving driver for LEDs with their hands on the PT4115 base with dimmer

Using PT4115 a driver circuit permits the use of several types of power sources: a voltage of 12 ÷ 240 12 ÷ 18 and in in the second case in the general scheme of the LED driver PT4115 must enter the diode bridge with a capacitor mounted on output.

driver manufacturer for LEDs with their hands

Illustration	Description of work
	you can take the old in order to facilitate the work Power Supply from a mobile phone.
	The apparatus is in fact voltage regulator and it incorporates almost all the radio for connecting multiple-watt LEDs.
	From the scheme must vypayat limiting resistor, which protects the phone from excessive supply voltages. In this case, the 5 kOhm resistor disposed at the output channel.
	In place of the static resistor needed to solder trimmer. Initially, it is expedient to put on the same 5 ohms. In the process of setting the voltage can be raised to the desired level.
	To the output channel 3 LEDs connected in series. Provided that they have a power of 1 watt total power consumption at the output be 3 watts.
	remove from the board input pins if necessary.
	Installed in their place the wires from the power cord to the 220V.
	Preferably in solder gap 1 ohm resistor. Its function - increase of the LED attenuation range.
	After assembly, check the efficiency of the entire system. (LEDs are not yet lit)
	Turn the trimmer, are making light LEDs.

Attention! Checking modified apparatus must be extremely careful, you can get an electric shock in 450

For more information on how to make the driver for the LED lamp 220 according to the scheme with their own hands can be found on the video:

At what price you can buy a driver for LEDs

Drivers for LEDs are implemented in radio parts stores. In addition, quite a large range of different sites offer: as specialized implementing electrical engineering, and general business area. Cost depending on performance can vary over a considerable range of 100 dot 3500 RUB.

As the table shows, the cost drivers is readily available and a special need for their independent manufacturing no.

We will be happy if you share with us your opinion on the use and arrangement of LED lighting.