How to connect LEDs to a 12 volt battery. Which LEDs are the brightest and most powerful?

LEDs are modern, economical, reliable radioelements used for light indication. We think everyone knows about this! It is based on this experience that there is such a high desire to use LEDs for the design of a wide variety of electrical diagrams, both in consumer electronics and for automobiles. But here certain difficulties arise. After all, the most common LEDs have a supply voltage of 3...3.3 volts, and onboard voltage the car is nominally 12 volts, and sometimes it rises to 14 volts. Of course, a logical assumption arises here that in order to connect the LEDs to the 12 volt network of the machine, it will be necessary to lower the voltage. The article will be devoted to this topic, connecting the LED to the vehicle’s on-board network and reducing the voltage.

Two basic principles on how you can connect an LED to 12 volts or reduce the voltage at the load

Before moving on to specific schemes and their descriptions, I would like to talk about two fundamentally different, but possible options connecting the LED to a 12 volt network.
The first is when the voltage drops due to the fact that an additional consumer resistance is connected in series with the LED, which is a voltage stabilizer microcircuit. In this case, a certain part of the voltage is lost in the microcircuit, turning into heat. This means that the second, remaining one goes directly to our consumer - the LED. Because of this, it does not burn out, since not all of the total voltage passes through it, but only a part. The advantage of using a microcircuit is the fact that it is capable of automatically maintaining a given voltage. However, there are also disadvantages. You will not be able to reduce the voltage below the level for which it is designed. Second. Since the microcircuit has a certain efficiency, the drop relative to the input and output will differ by 1-1.5 volts downwards. Also, to use the microcircuit, you will need to use a good dissipative radiator installed on it. After all, in essence, the heat generated by the microcircuit is the loss we have not claimed. That is, what we cut off from a larger potential in order to get a smaller one.
The second option for powering the LED is when the voltage is limited by a resistor. This is akin to taking a large water pipe and narrowing it. In this case, the flow (flow and pressure) would decrease significantly. In this case, only part of the voltage reaches the LED. This means that he can also work without the danger of being burned. The disadvantage of using a resistor is that it also has its own efficiency, that is, it also wastes unclaimed voltage into heat. In this case, it can be difficult to install the resistor on the heatsink. As a result, it is not always suitable for inclusion in a circuit. Another disadvantage is the fact that the resistor does not automatically maintain the voltage within a given limit. When the voltage in the common circuit drops, it will supply the same lower voltage to the LED. Accordingly, the opposite situation will occur when the voltage in the common circuit increases.
Of course, both options are not ideal, since when operating from portable energy sources, each of them will spend part of the useful energy on heat. And this is relevant! But what to do, this is the principle of their work. In this case, the power source will spend part of its energy not on useful action, but on heat. The panacea here is to use pulse width modulation, but this significantly complicates the scheme... Therefore, we will still focus on the first two options, which we will consider in practice.

Connecting an LED through a resistance to 12 volts in a car (via a resistor)

Let's start, as in the paragraph above, with the option of connecting the LED to a voltage of 12 volts through a resistor. In order for you to better understand how the voltage drop occurs, we will present several options. When 3 LEDs are connected to 12 volts, 2 and 1.

Connecting 1 LED through a resistance to 12 volts in a car (via a resistor)

So we have an LED. Its supply voltage is 3.3 volts. That is, if we took a 3.3 volt power source and connected an LED to it, then everything would be great. But in our case it is observed increased voltage, which is not difficult to calculate using the formula. 14.5-3.3= 11.2 volts. That is, we need to initially reduce the voltage by 11.2 volts, and then only apply voltage to the LED. In order for us to calculate the resistance, we need to know what current flows in the circuit, that is, the current consumed by the LED. On average, this is about 0.02 A. If you wish, you can look at the rated current in the datasheet for the LED. As a result, according to Ohm's law, it turns out. R=11.2/0.02=560 Ohm. The resistance of the resistor is calculated. Well, drawing a diagram is even easier.

The resistor power is calculated using the formula P=UI=11.2*0.02=0.224 W. We take the closest one according to the standard series.

Connecting 2 LEDs through a resistance to 12 volts in a car (via a resistor)

By analogy with the previous example, everything is calculated the same way, but with one condition. Since there are already two LEDs, the voltage drop across them will be 6.6 volts, and the remaining 14.5-6.6 = 7.9 volts will remain for the resistor. Based on this, the scheme will be as follows.

Since the current in the circuit has not changed, the power of the resistor remains unchanged.

Connecting 3 LEDs through a resistance to 12 volts in a car (via a resistor)

And one more option, when almost all the voltage is extinguished by LEDs. This means that the resistor will be even smaller in value. Total 240 ohms. A diagram for connecting 3 LEDs to the machine's on-board network is attached.

Finally, all we have to say is that the calculations used a voltage of not 12, but 14.5 volts. It is this increased voltage that usually occurs in the electrical network of the car when it is started.
It is also not difficult to estimate that when connecting 4 LEDs, you will not need to use any resistor at all, because each LED will have 3.6 volts, which is quite acceptable.

Connecting an LED through a voltage stabilizer to 12 volts in a car (via a microcircuit)

Now let's move on to a stabilized 12-volt LED power supply circuit. Here, as we have already said, there is a scheme that regulates its own internal resistance. Thus, the LED will be powered steadily, regardless of voltage surges in the on-board network. Unfortunately, the disadvantage of using the microcircuit is the fact that the minimum stabilized voltage that can be achieved will be 5 volts. It is with this voltage that you can find the most widely known microcircuits - stabilizers KR142 EH 5B or a foreign analogue L7805 or L7805CV. Here the only difference is in the manufacturer and the rated operating current from 1 to 1.5 A.

So, the remaining voltage from 5 to 3.3 volts will have to be extinguished according to the same example as in previous cases, that is, by using a resistor. However, reducing the voltage with a resistor by 1.7 volts is no longer as critical as by 8-9 volts. Voltage stabilization in this case will still be observed! Here is a wiring diagram for the stabilizer chip.
As you can see, it is very simple. Anyone can implement it. No more difficult than soldering the same resistor. The only condition is the installation of a radiator that will remove heat from the microcircuit. It is necessary to install it. The diagram says that the microcircuit can power 10 LED circuits, but in fact this parameter is underestimated. In fact, if about 0.02 A passes through the LED, then it can power up to 50 LEDs. If you need to provide power to a larger quantity, then use a second identical independent circuit. Using two microcircuits connected in parallel is not correct. Since their characteristics are slightly different from each other, due to individual characteristics. As a result, one of the microcircuits will have a chance to burn out much faster, since its operating modes will be different - overestimated.
We have already talked about the use of similar microcircuits in the article “5-volt charger in a car.” By the way, if you still decide to power the LED using PWM, although it’s hardly worth it, then this article will also reveal to you all the secrets of implementing such a project.

To summarize about connecting an LED to 12 volts in a car with your own hands

To sum up, about connecting an LED to a 12 volt network, we can say about the simplicity of the circuit design. Both with the case where a resistor is used, and with a microcircuit - stabilizer. All this is easy and simple. At least this is the simplest thing you can come across in electronics. So everyone should be able to connect an LED to the car’s on-board 12-volt network, for sure. If this is too tough, then you shouldn’t take on something more complex at all.

Video on connecting an LED to a network in a car

And now, to make it easier for you to estimate what resistance value you need and what power for your specific case, you can use the resistor selection calculator

The most correct connection several LEDs - sequential. Now I will explain why.

The fact is that the determining parameter of any LED is its operating current. It is the current through the LED that determines what the power (and therefore the brightness) of the LED will be. It is the excess maximum current leads to an excessive increase in the temperature of the crystal and failure of the LED - rapid burnout or gradual irreversible destruction (degradation).

Current is the main thing. It is listed in technical specifications LED (datasheet). And depending on the current, the LED will have one voltage or another. Voltage can also be found in the reference data, but it is usually indicated in the form of a certain range, because it is secondary.

Serial connection

When LEDs are connected in series, the same current flows through them. The number of LEDs does not matter, it could be just one LED, or it could be 20 or even 100 pieces.

For example, we can take one 2835 LED and connect it to a 180mA driver and the LED will operate normally, delivering its maximum power. Or we can take a garland of 10 of the same LEDs and then each LED will also work in normal passport mode (but the total power of the lamp, of course, will be 10 times greater).

Below are two LED switching circuits, pay attention to the difference in voltage at the driver output:

So to the question of how the LEDs should be connected, serial or parallel, there can only be one correct answer - of course, serial!

The number of LEDs connected in series is limited only by the capabilities of the driver itself.

Ideal driver can endlessly increase the voltage at its output to provide the required current through the load, so an infinite number of LEDs can be connected to it. Well, real devices, unfortunately, have a voltage limit not only from above, but also from below.

Here is an example of a finished device:

We see that the driver is able to regulate output voltage only within 64...106 volts. If to maintain a given current (350 mA) you need to raise the voltage above 106 volts, then it’s a bummer. The driver will output its maximum (106V), and what the current will be is no longer dependent on it.

And, conversely, you cannot connect too few LEDs to such an LED driver. For example, if you connect a chain of 10 LEDs connected in series to it, the driver will not be able to lower its output voltage to the required 32-36V. And all ten LEDs will most likely just burn out.

Availability minimum voltage is explained (depending on the circuit design) by limitations on the power of the output control element or by going beyond the limiting generation modes of the pulse converter.

Of course, drivers can be for any input voltage, not necessarily 220 volts. Here, for example, is a driver that converts any source permanent voltage (power supply) from 6 to 20 volts into a 3 A current source:

That's all. Now you know how to turn on an LED (one or more) - either through a current-limiting resistor or through a current-setting driver.

How to choose the right driver?

Everything is very simple here. You only need to choose according to three parameters:

1. output current;
2. maximum output voltage;
3. minimum output voltage.

Output (operating) current of the LED driver- this is the most important characteristic. The current should be equal to the optimal current for LEDs.

For example, we had 10 full-spectrum LEDs at our disposal for:

The rated current of these diodes is 700 mA (taken from the reference book). Therefore, we need a 700 mA current driver. Well, or a little less to extend the life of the LEDs.

Driver maximum output voltage must be greater than the total forward voltage of all LEDs. For our phytoLEDs, the forward voltage is in the range of 3...4 volts. We take it to the maximum: 4V x 10 = 40V. Our driver must be able to output at least 40 volts.

Since ultra-bright light emitting diodes (LEDs) became available to a wide range of consumers, they have immediately attracted great interest. Based on LEDs, you can create many interesting lighting designs. However, connecting an LED to 12 volts is fundamentally different from connecting the same incandescent lamp to 12 volts. This material will describe in detail how to connect light-emitting diodes to power supplies with different voltages.

What LEDs are connected to 12 volts?

To briefly answer the question posed as a subtitle, the answer will be: none! To a non-specialist, such an answer will seem paradoxical, because there are LEDs on sale that, as sellers say, are designed to be powered by a 12-volt source.

Let us undertake to assert that only LED-based products can be designed for a specific voltage. It is not correct to talk about a specific LED operating voltage. This is due to the physical processes occurring in it when light is emitted.

The main characteristics of these processes are the operating current and the maximum permissible current of the device. Reference books and datasheets indicate the voltages on the LEDs when operating current flows. These values ​​are used for calculating LED designs, and not for selecting a power source.

By the way, the voltage in operating mode only ranges from 1.5 V to 3.5 V. The value depends mainly on the color of the emitted LED. Lower voltages drop on red LEDs; higher values ​​are considered super-bright. Commercially available 12 volt light emitting diodes are not isolated devices.

Twelve-volt LEDs are matrices consisting of several light-emitting diodes. Matrices are LED assemblies assembled from chains of sequentially connected devices.

Each matrix has several chains that are connected in parallel to each other. When they say that an LED is designed for twelve volts, they mean that the voltage drop across a series chain of them when operating current flows is approximately 12 V.

Connecting super-bright and powerful LEDs to 12V

First, let's look at how to connect one powerful, super-bright LED to 12 Volts. Let's say we have at our disposal a device whose operating current is 350 mA. At the same time, the voltage drop across it in operating mode is approximately 3.4 Volts. It is easy to calculate that the power consumption of such a device is 1 W.

It is clear that you cannot connect it directly to 12 Volts. We will have to somehow “extinguish” some of the tension. In the simplest cases, quenching (current-limiting) resistors are used for these purposes. It is connected to the LED in series. The power supply circuit for one LED is shown in the photo.

R=(U supply – U slave)/I slave.

In our example, the power will be about 3 watts. It is quite difficult to find a resistance of such power, so two 100 Ohm resistors with a power of 2 W, connected in parallel, can be used as a quenching resistor.

In principle, based on these calculations, it is already possible to create a practical design. By connecting the LED to 12V via a switch, you can organize additional lighting for the car’s engine compartment, trunk or glove box.

We have shown that the creation of such a scheme is possible, but its application is irrational. It is easy to see that two-thirds of the power consumed by the structure comes from the quenching resistor and is therefore wasted. Below we will tell you how to avoid unnecessary losses.

How many LEDs can be connected to 12V?

Obviously, according to the simplest scheme, you can connect as many as you like to a 12 Volt source. The main thing is that the connected power source has enough power. However, we have seen that with such a connection scheme a lot of energy is wasted.

The simplest way out of this situation is to reduce the power dissipated by the current-limiting resistor. To reduce wasted power, several LEDs are connected in series and fed through a single quenching resistor. In this case, the voltage drop across the resistance is significantly less. Consequently, energy losses are significantly reduced. Calculation of resistance for series connection of light-emitting diodes is performed using the formula:

R=(U supply – nU slave)/I slave.

Where n is the number of LEDs connected in series.

In the case of a 12 Volt source, it is reasonable to connect three LEDs and one quenching resistor in series. The voltage drop across the LEDs will not exceed 10.5 Volts and only 1.5 Volts will remain for the resistor.

This technical solution widely used when the number of LEDs connected to 12 Volts is a multiple of three. That is, you can connect 6, 9, 12, ..., 3N LEDs this way. For example, this is what manufacturers of LED strips do. In them, the LEDs are grouped in groups of three and are powered through one common resistance.

If you need to connect 4 LEDs to 12 Volts, then it is advisable to group them by 2, and feed each pair through a current-limiting resistor.

LEDs with the same operating current should be connected in series. Otherwise, different devices will shine with different brightness or the current of any LED will be exceeded, and it will fail.

As for connecting LEDs “rated for 12 V,” it is better to establish their “operating voltage” experimentally. To do this they need to be connected to laboratory block power supply and, gradually increasing the voltage, control the current consumption. The voltage at which the operating current will be reached can be used to calculate the current limiting resistor.

How to connect LED to 3 or 5 volts

Most low-power LEDs operate normally at 3 and even more so at 5 volts. You can calculate current-limiting resistances for them using the above formula.

When manufacturing structures with autonomous power supplies, especially if they use ultra-bright “powerful” LEDs, this approach is not acceptable. The power dissipated by the quenching resistor significantly reduces the operating time of the device.

Therefore, modern hand-held flashlights powered by low-voltage batteries use electronic converters voltage - drivers. Losses in drivers are much lower than in current-limiting resistors. Drivers are now available and can be easily found in stores.

Having some knowledge of electronics and skills in working with a soldering iron, you can make a simple driver yourself. One of simple circuits converter for powerful LED is given below.

How to connect to 12 volt car

Connecting LEDs to the vehicle's on-board network does not differ significantly from connecting to other power sources. Just don't forget that accumulator battery A car in normal condition produces not 12 Volts, but approximately 14 Volts.

Even when connecting, you must remember that not every car has an on-board voltage stabilization system that works reliably. Therefore, when calculating quenching resistors, it is better to take the supply voltage equal to 15 - 17 volts. This will somewhat reduce the brightness of the glow, but will significantly extend the service life, since the LED will operate in a “gentle” mode.

Connection video

Before connecting, we recommend watching a good video to reinforce the knowledge gained. The author explains in detail and in accessible language how to connect an LED to 12 volts from a computer power supply, how to calculate a resistor and other nuances.

Results

In conclusion, the following considerations need to be taken into account when connecting ultra-bright LEDs:

• the most important parameter of an LED is its operating current;
• energy is uselessly dissipated on quenching resistors;
• by using a serial connection, you can reduce losses while simultaneously reducing the number and power of resistors used;
• in the car’s on-board network there is not 12 volts, but somewhat more, and for reliable operation of the connected light-emitting diodes, this factor must be taken into account.

Having remembered all the above connection aspects, you can easily power any LED, in any quantity, from any 12 Volt DC power source.

12 volts are a relatively new lighting source that has become widely used not so long ago. Our compatriots choose diodes because of their aesthetic beauty, as well as a longer service life. For more information on how diode elements are connected and what needs to be taken into account, read below.

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What does a car owner need to consider before replacing?

To do it yourself correctly, using the connection diagram, connect led light bulbs, first of all, you need to understand the basic information. First you need to understand that a 12-volt blinking car diode is not a lamp.

Connecting LEDs to a 12-volt on-board network should be done taking into account some points:

1. First of all, to secure the connection, you need to take into account the voltage that is present in the car electrical network. As a rule, this parameter is about 12-13 volts when the engine is off and about 13-14.5 volts when the engine is running.
2. On average, one bright and powerful diode requires 3.5 volts of power, but this figure can also vary depending on the color. For example, a yellow or red flashing LED for a car will consume about 2.3 volts, and white or blue elements will consume 3.5 volts on average.
3. Unlike standard incandescent light bulbs, LED assemblies provide better illumination of the surrounding surface, which is especially good for installation in dashboards.
4. Before purchasing, you should check the type of lens installed in the light bulb. There are highly targeted devices equipped with small lenses.
5. Regardless of the type, twelve-volt diode elements have both a positive and negative terminal. The positive contact in this case is the anode, and the negative contact is the cathode.

To choose the right 12V diode elements, you need to navigate their varieties, and they are divided among themselves by power:

1. Low-power devices do not have a cooling system, so their service life is usually short. In cars, it makes sense to use such devices only as indicators, for example, the inclusion of daytime running lights. running lights or when installing a battery discharge controller.
2. Powerful 12V diodes have a longer service life; if used correctly, they can last up to 10 years. It must be taken into account that such diode elements are not subject to heavy loads.
3. Modules Such devices are a steel plate on which a number of diode elements are mounted. The price of a module depends on its reliability and production quality - what better quality, the higher the price. The modules should not be confused with Chinese tapes, since their operation is possible, perhaps, to illuminate the control panel or glove compartment.

Instructions for connecting LEDs

How to connect an LED to your car? What resistance should be selected for the LED? Do I need to use resistors?

Below we will describe how the diode module should be connected:

1. The procedure for connecting LEDs to a 12-volt network begins with calculating the power supply. The main disadvantage of clusters is that their brightness will depend on changes in engine speed. If the rpm drops, the power will also decrease. Consider the fact that the most optimal indicator for a good glow of clusters is the voltage parameter of 12.5 volts - if it is lower, the glow will be weak.
2. The cluster design includes diode elements and a resistor, which, by the way, is an important component of any cluster. The resistor device used to absorb excess voltage is installed at the rate of one per three diode elements. So if you bought a whole strip to install in an optic, you will most likely need to cut it. Moreover, circumcision should be carried out only on certain segments.
3. The connection procedure is carried out in a sequential manner. That is, you will need to first make a cluster by connecting several diodes to each other in turn, and the ends of the cluster are connected to the on-board network. As an example, consider white diode components with a power of 3.5 volts. For a regular 12 V on-board network you will need three diode light bulb, which will consume a total of 10.5 volts. Daisy chaining means that the positive terminal of one component must be connected to the negative terminal of another.
4. There is no need to directly connect the cluster yet; a resistance, that is, a resistor, is connected in series. It should be taken into account that the resistance should be about 100-150 Ohms, and the resistor power parameter should be 0.5 W (the author of the video is the Auto Repair and Tuning channel).

Parallel connection method

To connect an LED to 12 volts in parallel, follow these steps (an example is considered with a 3.5 volt diode element and a current of 20 mA):

1. Measure the voltage where the light source will be connected to ensure that the connection will be effective. For example, this is 13 volts.
2. After this, 3.5 volts of the diode are subtracted from 13 volts, resulting in 9.5 volts. All measurements are made using Ohm's formula - in our case, 20 mA is divided by 100, resulting in 0.02 A.
3. The same formula is used to calculate the resistance; to do this, 9.5 volts must be divided by 0.02. As a result, we find out that we need a 475 Ohm resistor.
4. The next step is to calculate the power - you need to know this in order to prevent overheating of the resistor element. According to our parameters, 9.5 is multiplied by 0.02 - we get 0.19 W. To prevent possible failures, power can be taken in reserve.
5. Next, using a multimeter, the current is measured in the area between the diode lighting source and the resistor element. After this, the tester is set to 10 amperes, and the positive terminal of the device must be connected to the battery positive, the negative terminal to the lamp positive.
6. Ultimately, a reading of around 20 mA should appear on the multimeter display. Depending on the light source, as well as the resistance used, the parameters may differ.

Photo gallery “Diode connection diagrams”

Conclusion

What you need to consider for the system to work correctly:

1. To prevent the brightness of light sources from changing, you can additionally add a stabilizer to the circuit.
2. When connecting, you need to use high-quality resistance, since the efficiency of the backlight depends on the resistor. In addition, if you do not want to regularly change diodes, then they must also be of high quality.
3. If you are not sure that you can connect the backlight correctly, it is better to seek help from an electrician.
4. Before connecting, be sure to check the voltage in the on-board network - if it is low, then you need to check the functionality of the battery and generator.

Price issue

The cost of diodes differs depending on their type and purpose. For example, for one headlight lamp the car owner will have to pay from 300 to 5 thousand rubles. Conventional diodes for installation in dashboard cost about 75 kopecks apiece. A piece of diode strip 30 cm long will cost about 600 rubles.

Video “Features of connecting diode lamps in cars”

What needs to be taken into account and what mistakes should not be made - recommendations from a specialist in connecting diode lighting sources are given in the video below (author - Amateur Radio channel).

After the article about many questions from visitors disappeared. But another question arose - in particular: connecting LEDs to 12 V. For the most part, car enthusiasts are interested in this.

I want to make a diagram. which will allow you to power 1-3 LEDs in parallel from 12 V. Using one of online calculators I calculated that I need 2 resistors - 100 and 33 Ohms. After assembling the 100 ohm circuit, the resistor overheats and fails. What needs to be done to prevent the resistor from overheating? Both resistors are 1/2 W. LEDs 3.6 V. Andrey P.

Of the many questions, I chose one, the most interesting. And I’ll try to explain in a more popular way the process of connecting LEDs to 12 V.

Connecting LEDs to 12 V using a simple scheme

This scheme is not suitable for our purposes; there will be no division in the proportion of 1 to 4.

We need to either use three LEDs connected in series with one resistor, or if you still want a parallel connection, then a resistor must be installed at each LED.

In my case, I would take a resistance of 20 mA. This is the most optimal solution. In general, resistors need to be selected based on a specific type of LED.

Connecting LEDs to a car battery from 9-12-16V

The connection diagram discussed above is very simple and assumes that you have 12 V DC.

Earlier, I already made a reservation that most questions are asked by car enthusiasts, and this of course implies connecting any LEDs to the car battery. Most batteries operate at a nominal 12V, but battery voltage varies from 9V to 16V during operation.

Let's take a simple example - the voltage drop across the LED is about 3.5 V at a current of 100 mA. therefore we have a power of 0.35 W (Power = Current x Voltage).

For an LED this will not play a big role, because we still have 12.5 V, which we can use somewhere else, using, of course, a resistor: (16V - 3.5 V) * 100 mA = 1.25 W.

Nominal battery voltage 12 V

Nominal Calcluations (i.e. Vbattery = 12V):

Pled = 3.5 V * 100 mA = 0.35 W (same as before)

Presistor = 8.5V * 100mA = 0.85W

To avoid excessive voltage drop across the resistor, you can use the circuit (shown in the first part of the article). However, it is worth remembering that if the battery is discharged and close to 12 V, then the likelihood is high that your LEDs connected to 12 V simply will not light up.

3.5V + 3.5V + 3.5V + Current*Rresistor = pretty close to 12V.

Connecting LEDs to 12 V using two resistors

You can connect LEDs to 12 V using not one but two resistors. The scheme is not much more complicated, but it is safer and “more efficient”.

Each line connects bipolar transistor. In the first line we see that the base is shorted to the collector and emitter and to ground. All bases are connected to each other. As a result, the same current will flow through each line. It is not possible to guarantee one hundred percent performance, since temperature conditions can play a big role.

I'll repeat it again. that this scheme is “more secure”, because in this case, you don’t need to use large 2 W resistors, which get quite hot. Besides. Experimentally, you can adjust the brightness of the LEDs by selecting transistors.

Video of connecting an LED to 12 volts

I understand that most will not understand all this. what is written here. therefore, for those who just want to see and repeat - watch the video, which popularly shows how to connect LEDs to DC 12 Volt.