DRL control on a microcontroller. DRL regulator without the use of complex microcircuits. Connecting the daytime running lights unit

The DRL controller is a device used to monitor the performance of daytime running lights. With the help of this device, more stable and optimal operation of the optics is ensured, which allows optimizing the functionality of the electrical network as a whole. You can learn more about how to build such a device at home from this article.

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DIY options

If you decide to build a daytime running lights controller for your car, then first we suggest you familiarize yourself with several options for manufacturing the device.

Photo gallery “Schemes for manufacturing”

1. Relay-based DRL controller. On many Vehicle Yes, standard fog lights are installed, but not all motorists use them. The reason may be the lack of need for operation, high voltage consumption of the optics, or its inefficiency. Alternatively, if necessary, the fog lights can be converted into daytime running lights, only the lighting sources will need to be replaced with diode ones. You will also need to slightly change the standard connection diagram; most likely, in this case you will need to dismantle the bumper and control panel.
   When you can access the on-board network, the connection procedure is carried out according to the diagram above. In this case, you need to provide correct work optics - that is, the running lights should automatically turn on when you start the engine and turn off when you turn on the dimensions or high or low beam. To ensure this, the signal from the side lights can be taken from the button illumination, thanks to this you will not forget to deactivate the DRLs.
2. Using ATmega8 board. This option is more preferable if access to the wiring in the car is difficult. The daytime running lights themselves are purchased separately; you do not need a control unit. You need to install the DRL into the bumper yourself; to do this, make the appropriate holes and fix the optics. After completing these steps, you will only have to work with the controller itself.
   It should be noted that this board also allows you to implement other, no less useful features, for example, an indication of the operation of the engine heater. In this case, the operating algorithm will be as follows: when the vehicle is not started, the voltage on the battery will be less than 13.5 volts. Accordingly, when the engine starts, the battery will be recharged, which means that the voltage will be more than 13.5 volts. The DRLs themselves will be activated automatically. To make the connection, two wires must be connected to the battery, and two to the optics itself.

Instructions for manufacturing the DRL regulator

Let's consider the process of making a regulator for DRLs at home in accordance with the diagram above.

The operating logic of this device is as follows - the unit activates the daytime running lights only in this case:

• if the car’s power unit is started;
• if the side lights and high and low beams are turned off.

Actually, these conditions are mandatory and meet all the requirements for the operation of daytime running lights. When you turn on the low beam at night, the controller will automatically turn off the running lights.

To make a block according to the diagram you will need the following elements:

• two bipolar transistor, in the diagram are designated as VT1 and VT6;
• three rectifier diode elements, marked as VD1, VD2, VD3;
• two 1 kOhm resistor components R1 and R2;
• you will also need two 5.1 kOhm resistors - marked as R3 and R4;
• one 10 kOhm resistor element - R5;
• one 15 amp fuse and one 10 amp relay, marked K1 in the diagram.

All these spare parts can be purchased at any radio market, in the appropriate store or ordered online. There should be no problems finding the constituent elements of the circuit. The process of manufacturing the device itself should not cause problems - you just need to connect all the elements on the board in the manner shown in the diagram. The connection procedure is carried out using soldering. If you do not know how to solder, then it is better to contact a qualified electrician - any specialist with experience can solder such a regulator without any problems.

When soldering, be careful not to damage the components of the controller, as this may lead to its further inoperability. All parts must be securely soldered, since vibrations may occur when the car moves, and they, in turn, have a destructive effect on any moving elements. Especially if we're talking about about electronics.

After the device is made, it must be connected correctly:

• DDM - must be connected to the engine fluid pressure controller or to the parking brake;
• the +12 volt output must be connected to the generator device or the ignition switch, in particular, you need to connect it to the contact where voltage appears when the engine is running;
• dimensions - as you might guess, in this case we are talking about the positive contact of the side lights, the specific connection location does not matter;
• GND is the mass or body of the vehicle;
• DRLs are daytime running lights themselves with halogen or diode lighting sources (the author of the video about the connection is Vitaly Novakov).

As for setting up the manufactured controller, this process consists of diagnosing the operating algorithm as a result of applying simulation pulses to it. When 12-volt voltage is supplied to the parking light input, the relay should automatically turn off. It will also turn off if the oil pressure controller input is shorted to ground.

Price issue

If for some reason you do not want to make a controller at home, then you can always buy it on the market or order it on the Internet. Costs may vary by store, with price differences ranging up to 40%. On average, the cost of a DRL controller today ranges from 650 to 1000 rubles.

Video “Review of the DRL controller purchased in China”

The video below demonstrates detailed review Chinese controller for daytime running lights (the author of the video is Sergey Stanevich).

The device is designed to automatically turn on and off daytime running lights (DRL) when starting and stopping. Assembled on a simple and cheap PIC12F629 microcontroller. Has a sound alarm and other useful little things.

Brief operating logic of the device

1.Power supply 12V
2.When the ignition is turned on after 6 pulses from the speed sensor, the DRL is turned on
3.When the dimensions are turned on, everything goes into normal mode
4.When the dimensions are off, go to step 2
5.When stopping (for example, in a traffic jam), the DRL will turn off after 3 minutes when you start moving, step 2
6.When you stop and turn off the ignition, the DRL lights up for another 20 seconds and turns off (polite backlight).

Device operating mode:

1. When the ignition is turned off, the HL1 LED blinks at a frequency of 1 time per second (1Hz), indicating that the device is in standby mode (standby mode).

2. When the ignition is turned on, the HL1 LED starts to light constantly, the microcontroller waits for the arrival of pulses from the speed sensor, and when the car starts moving, after 1 second the DRLs automatically light up and remain on all the time until the vehicle stops.

3. During a stop, the DRL off time delay mode is activated (3 minutes), this is signaled by the built-in Beeper (2 short sound signals- this is when the ignition is turned on and the car is stopped), if you turn off the ignition switch at this time (for example, when parking for a long time), 4 short beeps will sound, signaling that the DRL time delay mode has turned on for 20 seconds and then they will turn off (polite mode backlight), the device goes into standby mode.

4. When the side lights are turned on, the device automatically goes into standby mode, the DRLs turn off (traffic rules), everything works as normal.

5. The polite backlight mode can be turned on as follows: turn on the ignition, 2 short beeps will sound, and immediately turn it off (4 beeps will sound), and the device will automatically switch to the polite backlight mode. If you need to turn off the DRL without waiting for the time delay, you should turn on and then turn off the side lights.

6. The HL2 LED signals the status of the DRLs (lit - DRLs are working, off - DRLs are not working)

Today we will make a regulator for the daytime running lights of a car without using complex microcircuits. Despite the fact that normal and individual operation of modern electronic devices is impossible without any auxiliary devices, scientists have proven in practice that such a phenomenon is still possible.

In electronics, a controller is a special control equipment. In the same industry, a microcontroller is a small component of a controller, the basis of which is an integrated circuit.

If the car is not equipped with factory daytime running lights, and the use of main headlights instead of unintended sources daylight- this is an unaffordable luxury for a car owner, then in the daytime, according to Russian traffic rules, fog lights can be used to highlight the car.

It only makes sense to use fog lights instead of main headlights in a situation where their lamps have a power less than that of the lamps in standard car headlights. The legislator does not yet oblige every car owner to install special daytime running lights on vehicles; however, by next 2016, daytime running lights will need to be installed on every vehicle.

Thus, the installation of daytime running lights on vehicles will be a prerequisite.

In order to correctly and safely install such equipment on a car, you will have to resort to the work of a professional technician from a car repair shop, or do all the work yourself.

From what design features has a car, and where the mounted equipment was manufactured (at the factory, or on its own) directly depends on the complexity of the work. For those who are installing daytime running lights on a car themselves, you need to know that such work is carried out in strict accordance with all regulations of the Russian Federation, namely clause 1.3.29 appendix. No. 5 to those. safety regulations for wheeled vehicles.

Relay base for daytime running lights controller

The majority of vehicles are equipped with factory fog lights, but some drivers do not use them at all due to the fact that such lights are simply not needed, consume a lot of energy, or do not work well. Such headlights should be converted into running lights. To do this, standard light bulbs will need to be replaced with LED ones. This circumstance will save electrical energy, and when calculating the electrical mnemonic diagram it will be possible not to take into account the current consumed.

Then you will need to make adjustments to the standard switching diagram. To do this, most likely, you will need to remove the bumper and instrument panel. According to the masters, such work takes a little more than one hour. As soon as access to the on-board electrical wiring is allowed, switching is performed according to the scheme:

It is extremely important that all running lights work properly: when the key is turned in the ignition switch in a certain way, which ensures the engine starts, as well as when the high or low beam headlights, side lights, or main headlights are turned on, the running lights should turn off. In order to remember to turn off the daytime running lights, the dimensions must be interconnected with the backlight. This convenient connection was appreciated by most drivers.

What to do in a situation where you can’t get to the wiring in the car at all, or it’s very difficult to do so? Without any exaggeration, many car enthusiasts will not be able to handle such work!

There is a solution - Atmega8.

Description of the Atmega8 device

Lighting equipment for daytime running lights and a control module can be purchased separately for a reasonable price. If the car bumper already has holes for installing fog lights, then you can fix the new device in them, but if there are no such holes, then they need to be carefully cut out. The lamps are attached to 4 self-tapping screws. Next we switch to working with the controller. We use a proven eight-bit microcontroller from Atmel - Atmega8.

Using this equipment, it is possible to use a number of auxiliary options, such as indexing the operation of the engine, which is turned off while the engine is running. The device operates according to a simple scheme: when the engine is not running, the voltage to the battery is less than 13.5V, and when the engine is running, the voltage is more than 13.5V and the battery is charging.

The running lights turn on automatically if you connect 2 wires to the battery and 2 wires to the DRLs. If properly installed, this medium-cost equipment will beautifully complement the overall exterior of the machine.

The DRL control controller can be assembled on a comparator basis.

The comparator here is made on the basis of a 2-channel operational amplifier (LM358). This circuit is not expensive and does not require the installation of a voltage stabilizer. The device is aimed at saving voltage (3-30 V).

This is such a tautology. But nevertheless, what is written, according to syntactic, spelling and semantic rules, has the right to life. Author's Note: A controller is an electronics control device; microcontroller - a miniature part of a controller based on integrated circuit.

If your car is not equipped with standard daytime running lights, and the use of main headlights is too wasteful for you, the Traffic Rules of the Russian Federation allow the use of fog lights to indicate a vehicle during daylight hours.

But this option is rational only if the power of the light bulbs in the fog lights is less than the power of the lamps in the main headlights. If this is not the case, then installing DRLs cannot be avoided. In general, on this moment, the installation of DRLs on a vehicle in service is not mandatory, but by 2016 all vehicles must be equipped with daytime running lights.

As a result, the conclusion suggests itself - definitely install DRLs.

To do this, you can use the services of a specialized auto center, or you can perform this not very complicated operation yourself. Of course, a lot depends on the car (the complexity of removing the dashboard and bumper) and on the origin of the DRL kit itself (factory production or homemade). It should be recalled that independently installed running lights must comply with the requirements of GOST R 41.48-2004 (UNECE Regulations No. 48 and No. 87) or clause 1.3.29 of Appendix No. 5 to the “Technical Regulations for the Safety of Wheeled Vehicles”.

Relay based DRL controller

Most vehicles have standard factory fog lights. But not all drivers use them. The reasons are different: there is no need, the headlights are too power hungry or simply ineffective. So they can be converted into running lights. Naturally, the light bulbs will have to be replaced with LED analogues. This will give good energy savings. energy and, importantly, will allow you to neglect the consumed current when calculating the electrical mnemonic diagram.

Next, you will need to change the standard switching circuit. This is where you will need (with a high degree of probability) to remove the dashboard and bumper. According to workers' reviews, this is done in just over an hour. After gaining access to the on-board electrical wiring, we switch everything as follows:

It is important to ensure the correct operation of the running lights: they must turn on when the ignition key is turned to a position that allows the engine to operate, and turn off when the main headlights or parking lights (dimensions) are turned on for the low/high beam. To do this, the size signal can be taken directly from the button illumination. This way you will never forget to turn off the DRLs. This scheme has been tested by many car owners and has no complaints.

But what to do if in a car, access to the wiring inside the cabin is extremely difficult or even impossible? For a lazy car enthusiast with an inquisitive mind, this will be a real obstacle. We need another solution. Let's consider the following option.

Option on ATmega8

DRL lamps can be purchased separately, without a control module, at a very reasonable price. There are already holes in the bumper (from the fog lights), if not, we cut them out. The entire installation consists of fixing the lamps with four self-tapping screws. It's up to the controller. In the proposed version, we will consider the use of the good “old” ATmega8, an 8-bit microcontroller from Atmel.

By the way, with its help it is also possible to implement additional functions, for example, an indication of the operation of the firewall, which tends to turn off when the car is running. The operating algorithm of the ATmega8 circuit is as follows: if the car is turned off, the voltage on the battery is less than 13.5 V, if it is started, charging is in progress, and the voltage is above 13.5 V.

The running lights turn on automatically.. Of the connections, there are 2 wires to the battery and 2 wires to the DRL. With careful installation, mid-price DRLs will fit very harmoniously into the exterior of the car.

There is also an option for assembling a DRL control controller based on a comparator.

DRL controller circuit on comparator LM358

In this circuit, the comparator is implemented on the basis of a low-power two-channel operational amplifier LM358. The circuit turns out to be very cheap, and besides, there is no need for a voltage stabilizer, unipolar power supply LM358 is designed for 3 - 30 V, again, saving. Schematic diagram Below, everything is simple and clear.

Setting up this controller comes down to setting the circuit's response threshold with a trimmer when the generator is operating, i.e. when the voltage in the on-board network is above 13.5 V.

Everything comes together very quickly and works reliably even in severe frost.

Many car enthusiasts have already heard about the benefits of DRLs and are starting to look for a decent model in stores. The assortment is widely represented by Chinese junk costing from 300 to 5000 rubles. Some don’t even understand why they should be installed on a car and buy junk for 500 rubles, which shines a little brighter than its dimensions, with a power of 2 watts. You've probably seen these, they still glow blue, and some of the LEDs don't light up or blink. Then they have the problem of how to wire up the running lights to make them last longer. Garage craftsmen offer various DRL connection schemes, the most difficult thing is to choose the right one.

Common names that will be used in the text: DRL "Daytime Running Lights", daytime running lights.

• 1. Types of connection
• 2. Operating mode
• 3. How to connect DRL with control unit
• 4. DRL controller
• 5. Select a stabilizer
• 6. Connection via relay
• 7. Other less popular methods
• 8. Installation check
• 9. Example of benefit

Types of connection

DRL Eagle eye, eagle eye

The connection diagram for running lights depends on the configuration and your budget. There are 3 types of configuration:

1. the most inexpensive, only DRL;
2. average in price, stabilizer included;
3. expensive, with a control controller.

If you have the cheapest and worst ones, then the kit does not include a controller or control unit. Such a unit performs the function of a voltage stabilizer and on/off control.

The average configuration includes a 12V voltage stabilizer. There are voltage surges in the car network, and LEDs really don’t like this and fail. The stabilizer will significantly extend the life of the LEDs. But in this option, you will have to choose a place for connection so that they turn on only when the engine is running. There are many places for this, for example an oil pressure sensor or a generator.

Domestic model

The expensive version is equipped with a control unit that connects directly to the battery in the car. According to the principle of operation, they are of two types:

• determine the difference between the number of volts when the engine is off and on;
• cheaper, it turns on when the voltage rises above 13V.

The best option is the first one, regardless of the voltage on your battery, always turn it on and off correctly. The second option is budgetary and does not always work. With the engine off, the number of volts must drop below 13V for the controller to turn off the DRL. However, if your battery is new or well charged, then even after stopping the engine, it will have a voltage above 13V for up to several hours. That is, the daytime running lights will not turn off on their own until there is less than 13V. The only drawback will be its own power consumption when the controller is waiting for the engine to start. It will discharge the battery along with burglar alarm.

Operating mode

According to technical regulations for cars, DRL should automatically turn on when the engine starts. When you turn on the low beams, they should turn off automatically so as not to dazzle at night.

There are also combined models with installed turn signals on sale. The turn signal duplication section is connected separately in parallel to the standard turn signals. Having a stable diet is also a must.

DRL with turn signal

For models with additional control, there is a follow-up backlight function that works for 10 minutes after the engine is turned off. It illuminates your path to your home or dugout, depending on where you live. Osram DRL has a mode in which they do not turn off, but dim by 50%. I just don’t know how legal it is and whether it will cause blindness.

How to connect DRL with control unit

DRL controller

I prefer the DRL connection scheme using the control unit, the most reliable way, suitable for any car and does not require any knowledge. Many car enthusiasts buy a DRL control unit from AliExpress - it is inexpensive, and the reviews seem to be good. However, most reviews are left either upon receipt of the product or after several days of use. In fact, absolutely all DRL controllers from AliExpress are short-lived and have the following disadvantages:

1. the operating principle does not comply with GOST;
2. there is no stabilization (for the majority);
3. low quality of materials and workmanship;
4. the features of the vehicle’s on-board network are not taken into account;
5. no guarantee;
6. some do not have moisture protection.

Of the quality options, I can highlight one from a Russian manufacturer, which fully complies with GOST and differs good quality. The DayLight+ controller also has built-in stabilization, which will significantly increase the life of the running lights.

Choosing a stabilizer

In this form, the first and second methods will be combined. Even if your daytime running lights do not have a stabilizer, I recommend purchasing one or making it yourself.

You can buy Chinese modules at prices ranging from 50 to 120 rubles, so as not to order on Aliexpress, take a look at Avito, you can find very reasonable prices. The most common modules are pulse LM2596 and linear LM317. They are of course outdated, but they will draw a current of 1 ampere, which will be a power of 12 watts.

The XL6009, XL4015 chips are considered modern for 2016. They have higher efficiency and heat up much less. They can withstand a current of 2 Amps without a chip cooling system, this is equivalent to a load of 24 watts.

Connection via relay

On forums and websites you will find different ways How to connect daytime running lights with your own hands, it will be different for each brand. Specialized relays are also sold, for example Forget-me-not, designed for any car.

The operating principle is simple. Power to the daytime running lights is supplied from the ignition switch wire. The positive wire from the far and near breaks the circuit when voltage appears on it. A 5-pin relay is sufficient for this. First, look for a solution on forums that specialize only in the make of your car. Perhaps you will find a simpler solution.

For example, in Duster you can connect the DRL to the cigarette lighter; voltage is supplied to it only when the ignition is turned on. This is better than looking for the ignition wire in the wiring. In any case, I recommend installing a fuse in case of a short circuit.

Many circuits use a gauge wire to disable the DRL. This is incorrect DRL should not go out when the headlights are turned on, only when low beam is on.

Another type of connection diagram for daytime running lights is the installation of a relay in the standard relay block of a car without any upgrades. It includes 30% or 50% distant, which will be enough to identify vehicles on the road. If the distant one consumes 120W, then 30% equals approximately 36W, 50% equals 60W.

Other less popular methods

Many people are interested in how to connect DRLs without a relay on their own, but it depends on the electrical system of your car; look for a solution in online clubs dedicated to your car. The most important thing is that power is supplied to this place after the engine starts.

The basic diagram for connecting the DRLs is through a 4 or 5 contact relay, which turns off when the low one is turned on. Those who are not too lazy to rummage through the car’s wiring can connect it from the oil pressure sensor or generator. On any vehicle, when the engine starts, the oil pressure light on the dashboard lights up, the signal from this wire is used to supply power. The second way to connect running lights yourself is to connect to a generator. They will turn on automatically when voltage appears on the generator.

Verifying the installation

Most car owners, after connecting the running lights with their own hands, like to take a photo of their junk. To make it less dim, they do this at night from close range. Due to their illiteracy, they do not know that they need to check in sunny weather from a distance of 100 meters. That's why they are called daytime and not nighttime.

Example of benefit

When traveling short distances in winter, especially in severe frost, a large number of Battery energy is wasted to start the engine. Over time, the battery loses its capacity and holds its charge worse. Using DRLs instead of low beams will allow you to charge the battery faster while driving.

Let's do the math:

1. low beam consumes about 100W, 2 lamps approximately 50W each;
2. decent DRLs up to 15W;
3. 100W – 15W = 85W less energy will be consumed.

For example, in my Duster there is a standard heating element that heats the interior until the engine warms up. Accordingly, the car will warm up faster.