Environmentally Friendly LED Lighting Components

Generally, we can say that LEDs are environmentally friendly and recyclable. They have a long lifetime and low power consumption. They don’t contain hazardous substances, for example, mercury as compact fluorescent lamps do. In this blog post, I will present to you four environmentally friendly luminaire component choices.

LED That Don’t Need a Driver

Have you ever looked inside the driver? In the picture above, you can see the inside of the small-sized one. Drivers are made of many different materials and components. That’s why they are hard to recycle. The fewer components product has, the easier it is to recycle. For example, an aluminium heatsink is easy to recycle, because it contains mainly aluminium.

Drivers are the most fragile parts of the luminaire. In general, they can be the first component that breaks from the luminaire.

All traditional LEDs needs a driver to work. Except for AC COB that can be connected straight to the mains power. Because AC COB doesn’t need a driver, luminaire can be a lot smaller than before. This gives more flexibility for the design. At the same time, you can save in logistics and packing. You can read more about AC COB from our blog post.

Same Lumen Output with a Smaller Luminaire

Size is an important feature when designing environmentally friendly luminaires. When you use less material the luminaire gets smaller. And by downsizing the luminaire you can save in logistics and packing.

One great way to make the luminaire smaller is Citizen’s HC COB. It has higher efficacy and lower terminal resistance. This means that you can use a smaller heatsink. Therefor luminaire gets smaller the and you can still get the same lumen output. As a result, it makes HC COB more environmental choice. Read more about HC COB from here.

The Right Amount of Light and Less Light Pollution with Right Optics

When we talk about LEDs, often we come up with light pollution. We can say that almost all outdoor light that doesn’t have a purpose is light pollution. This means that light always needs a target.

When you replace the old light sources (for example HPS-lamps) with same powered LED, you get a lot more light. This is not environmentally friendly. You get a lot of unnecessary light and same time create light pollution.

When we design luminaires with the same lumen output than before, LED saves energy. This is because LED has less than 10% of the incandescent lamp’s power consumption. That’s why it is important to think about lumens, not power when replacing lamps with LEDs.

LEDs light comes from a very small area and from a flat surface, so it is easier to control than a light bulb. In street lights, most of the light pollution comes from light that goes up and away from the road. It is important to choose optics for the luminaire which are designed to minimize the light pollution.

Control the Luminaires with Sensors

There’s a lot of different sensors for different applications. The most familiar ones are the on/off-sensors. They automatically switch the light >on and off  by movement. They save energy, as the light can never be accidentally left on. This type of sensors is already generally used in public spaces.

Another great way to save energy is to use daylight sensors. They react to the light that comes from the outside. This way you can maximize the benefits of the sunlight. For example, during the day, you don’t need as much artificial light as in the evening. Read more about sensors from this blog post.

We have already made big steps in ecology, but still, we have a lot to do. We need to think about the packing of the luminaire and logistics. It’s important to minimize the amount of plastic used in packing. Also, we need to think alternatives for air freight. Small choices really matter.

Below you can download a presentation about Citizen’s AC COB. If you have anything to ask, you can always email to me: taru.matikainen@light.fi

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Million shades of white LED

Nowadays LEDs have great efficacy and lifetime. They produce more and more light with less power. I think that it’s less important to increase efficacy because we have already reached what the market demands. What else we need from the light than a lot of lumens? In this blog post, I’ll compare the differences between white LEDs.

We all know that LEDs are available in different color temperatures. For example, Citizen 6 generation’s LEDs are available from 2700K to 6500K. They are also available in different color rendering indexes. Color rendering index simply means how well a white light source can show, or render, colors compared to sunlight. We know that the color rendering index does not always tell the whole truth (You can read more from this blog post).

Nowadays we need a light source that has good efficacy and color rendering, and it doesn’t hurt if the light source can be customized to use in many different luminaires. We want light source that brings colors vivid and alive. Also, design interiors with relaxing atmosphere.

Let’s look into what else affects the quality of light than the color rendering index and color temperature.

White without greenish tone

IMAGE: Black line in the picture is B.B.L. Red circles indicate below B.B.L. LEDs.

In some projects, we want a light source that makes white look whiter. Some LEDs may turn white into light green. Traditional white LEDs’ color temperature chromaticity is on or very near B.B.L. (Black Body Locus). Citizen also produces below B.B.L. LEDs. Their color temperature is below the B.B.L. line. As you can see in the picture, above the line is greenish colors and below the line is reddish colors. Below B.B.L. LEDs make white look pure white and it also renders red colors better. This way we can create light that doesn’t have a greenish tint.

Below B.B.L. LEDs are very popular in shop lighting and everywhere where brisk atmosphere is needed.

Read more about the color temperature from this blog post.

More attractive display with high color contrast

The general color rendering index (CRI) is defined as an average of the sum of first eight R-values. However, these first eight indexes are rather less saturated colors, while indexes R9-R12 represent highly saturated colors. This means that the same CRI doesn’t mean same color rendering.

The Citizen’s Vivid LEDs make colors seem brighter with better color contrast. The spectrum of light has been designed to have as good as possible saturation. This way Vivid LEDs can render bold colors vividly. With better saturation, you can read easier for example newspaper under the Vivid LEDs.

Below you can see a picture where Vivid LEDs are compared. The higher the bar is, the better the color renders. The comparison is done to halogen bulb (0= halogen bulb performance).

Great use for Vivid LEDs are places where good color rendering and concentration is needed, for example, clothing and cosmetic stores, art galleries, schools, hospitals, and offices.

There are two different Vivid LEDs:

  • Brilliant Vivid – Very high color contrast.
  • Natural Vivid – High color contrast.

Vivid LEDs are meant to be combined. Use Brilliant Vivid as spotlights to bring color and textures up, and Natural Vivid as base light because it has better efficacy but has still very good color rendering and contrast.

Change the color temperature of light

Everyone is now talking about “human-centric” -lighting in the lighting industry. It means that by changing the color temperature you can maximize productivity and improve concentration or create comfortable atmospheric feeling. Citizen’s Tunable White is a great solution for “human-centric” -lighting. Its color temperature can be changed freely from 2700K to 6500K. This means that you can achieve warm light like incandescent lamp and daylight with only one module. In addition to changing the color temperature, you can also dim the brightness.

Early Tunable White products have been big sized modules. Citizen’s Tunable white is as small as the COB. This means that you can make a lot of smaller Tunable White luminaires than before. The small size also gives more even light. The spots between cool and warm dies are practically invisible, which guarantee more smoothly light.

By connecting Tunable White into the right control unit, you can change the color temperature and brightness according to the time of day.

Light that gets warmer by dimming

One of the features of the halogen lamp is that when dimmed its color temperature changes warm-toned. Citizen’s Dim-to-Warm COB-LED does the same thing.

Dim-to-Warm is a COB-LED, so you don’t need any complicated special features from the driver, like two-channeling or programming features. Ordinary triac dimmable driver is enough. Dim-to-Warm COB has preset dimming curve, so when you dim it, its color temperature changes automatically just like halogen.

I hope that this blog post gives you some new thoughts for designing the luminaires. When you use any of the LEDs that I just presented to you above, you’ll get a luminaire that has more to provide than just ordinary light source. This way you can have competitive advantage.

You can download presentation about Citizen LEDs below. If you have anything to ask, please do not hesitate to contact me. My email address is taru.matikainen@light.fi and I’m always happy to help you.

Download Here

Downsize your luminaire with new HC-series

New series of LED, Citizen High Current COB LED is now available. What is High Current COB LED or in other words HC-COB? What new possibilities does it give to us? I’m going to tell you all that in this blog post.

HC-COB is COB that has same LES and package sizes as the previous Citizen generations. Compared to previous generations the HC-COB has higher efficacy and Tc and wider wattage and lumen range.

With new Citizen HC-COB, you can achieve lots of great advantages compared to previous LED-generations. You can downsize luminaire or get more lumens with the same size of the luminaire. So, there’s a possibility to use it in different ways. Let’s get into that.

Downsize your luminaire

Luminaire downsizing has become a trend in the luminaire industry. Nowadays luminaire size must be as small as possible to design luminaires that are cost-effective with less visibility. In public spaces, track lights are in general use. When you downsize those luminaires, you get space that is more spacious and airy.

HC-LED has higher efficacy and maximum Tc. So, you don’t need so large cooling system with it. This means that you can use a smaller heatsink to downsize the luminaire. Same time you can reach same lumens as today.

Luminaire downsizing means that you can make big savings, for example in aluminum, logistics and packing. As a result, it makes HC-COB more environmental choice.

At the same time when luminaire gets smaller, you can reduce system cost of luminaire. Smaller heatsink is cheaper than the bigger one. And as I said before, we can make big saving in packing materials and logistics when luminaire gets smaller. See the diagram below about how you can save in luminaire system cost.

As a result, you can make lighter and cost-effective luminaires that are more environmentally friendly.

Here’s an example of luminaire downsizing. In this example, we are changing COB version 6 to HC-series. The result is that you can get even more lumens with less LEDs.

Get more lumens from your luminaire

What if you don’t want to downsize your luminaire? Do you want more lumens with the same luminaire? With HC-COB that is possible too.

When you keep the same heatsink or luminaire design and just change the LED to HC-COB, you can get more lumens. This gives you more lumen package options and flexibility in one luminaire design.

Let’s see an example if COB version 6 is replaced by HC-series.

As shown above, you can get even 17,8 % more lumens with HC-COB.

What kind of lumen packages does HC-COB offer?

  • 2700K, 3000K, 3500K, 4000K, 5000K and 6500K
  • Ra70, 80, 90, 97 and Below BBL
  • Lumen range from 500lm up to 77 000lm
  • Same size than previous COB generations

Are you interested in more technical information? Download datasheet below or contact to our specialist. We’ll be ready to help you.

Download Here

Tunable White – Achieve color temperature from 2700K to 6500K with one LED module

Tunable White color changing

The Tunable White is becoming a big trend in residential and office lighting. I introduced one color changing LED product, Dim-to-Warm LED, in the earlier post.  In this post, I will tell you about the Tunable White module. Its color temperature can be changed freely from 2700K to 6500K. This means that you can achieve warm light like incandescent lamp and daylight with only one module. In addition to changing the color temperature, you can also dim the brightness.

Why color changing and Tunable White is a trend? How does it impact humans?  Let me shed light on that.

As we know human mind reacts to brightness and temperature of light. Cool light (e.g., daylight) has a refreshing effect and helps us work at school, office, where ever effective work is needed. Where cool light refreshes, the warm light has a comforting and relaxing effect. Naturally, these lights are presented in daytime during sunrises and sunsets.


Tunable white color chart


How to use Tunable White?

With Tunable White module, you can create better environments for both working and living. You can maximize productivity and improve concentration. Here are just some examples of the usage, but really there are countless ways to use Tunable White. 

One great use for Tunable White is offices. You need a lot of concentration to work effectively. This can be achieved with decent lighting. With this module, as said before, you can control the cool and warm light and dim the brightness. This gives the opportunity to select the right color temperature for office during the daytime.

In residential usage, Tunable White gives a possibility to simulate circadian rhythm. Connect the Tunable White to a control unit, it can change the color temperature automatically by daytime. This way you can enjoy cold refreshing light by midday and get the comforting feeling of warm light by evening.

Now we know some examples, but what kind of luminaires Tunable White is suitable for? Tunable White module is very small sized. This gives options to use it in the wider range of luminaire types.

Here are some examples:

  • Downlight
  • Spotlight
  • Indirect lighting
  • Table light
  • Decorative light

How does it work?

Citizen Tunable White module is made by using “multi-chip” technology. That means it’s made of tiny LED chips that are combined into the same module. Because of its very small size (LCN-C01A is only 15×15 mm), smaller luminaires can be made than before. The small size also gives more even light. The spots between cool and warm dies are almost invisible, which guarantee more smoothly light.

It is made from cool (6500K) and warm (2700K) diodes. The color temperature changes by controlling the output of the two different colored LEDs. LED’s brightness depends on the current; reducing the current the brightness reduces. These features give the option to dim and change the color temperature of LED.

Color curve of Tunable White module.

The Tunable White module has linear color curve because it has two primaries (6500K and 2700K). Advantages of two primaries are greater efficacy and simplicity. As seen in the diagram above, the linear color curve is located under the Black Body Locus (B.B.L.). That affects the color of the light and brings some colors up. You can get white light without greenish tint. This improves contrast in other colors.

A suitable driver needs to have two channel outputs to control CCT and intensity of the light. So, you need 1-10V, DALI or another two-channel driver to control the Tunable White luminaire.

Our high-quality Moons S Series Intelligent Drivers have great compatibility with the Tunable White module. They also have deep dimming from 100 % even to 0,1 %. You can program correct tuning and dimming curves for your luminaire. With Moon’s drivers, you can get everything out of this LED module.

If you have anything to ask, please don’t hesitate to contact us. For more information please download the presentation and the datasheets link down below.

Download Here

Dim-to-Warm – COB LED that dims like halogen


Dim-to-Warm is COB LED which works like halogen lamp when dimmed. Its specialty is that when you dim it the color temperature gets warmer. Usually dimming does not affect the color temperature of the LED. Dim-to-Warm LED imitates the effect of the halogen lamp which gets warmer by dimming. With full power you can get color temperature 3100K and at lowest 1850K.

Dim-to-Warm LED suits especially highly for decorative luminaries, for example used in restaurants, hotels, cruise cabins and home interiors. It’s perfect for space where you want to have dimmed and warm toned atmospheric lighting.

LED has great advantage compared to an incandescent lamp. Its power consumption is less than 10% of the incandescent lamp’s power consumption.

The color temperature of candlelight, incandescent and halogen lamp.

The color temperature of candlelight, incandescent and halogen lamp.


There are seven different packages from 900 to 3000 lumens. You can download more information about the product here.

Where and how to use?

Dim-to-Warm LED is great for places where you want the light that dims like halogen or incandescent lamp. You can use it for example for restaurants, hotels, cruise cabins and decorative luminaires where you have been using halogens before.

It’s easy to use. You can use Dim-to-Warm LED for all the luminaires where you have been using COB LED or you can use it to replace led modules. All optics, lenses and reflectors that are compatible with COB LED, suit also for Dim-to-Warm LED. LES area is CLC20-series for 9,8 mm and at CLC30-series for 15,2 mm.

How Dim-to-Warm works?

As we know, usually LEDs don’t change the color when you dim them. They always retain approximately the same color temperature when the brightness is reduced. LED’s brightness depends on the current; reducing the current the brightness reduces.

Dim-to-Warm LED is made from cold and warm LED areas. It has an internal control circuit which dims the cooler area first and later starts to control current of the warm one.  The color temperature gets warmer when dimmed.  This way the dimming works similarly in incandescent or halogen lamp.

The diagram below shows how the color temperature gets warmer when led is dimmed down and the current and brightness reduces (black color). You can also compare it to halogen lamp (grey color).


Dim-to-Warm is a COB LED, so you don’t need any complicated special features from the driver, like two-channeling or programming features. Ordinary triac dimmable driver is enough. We have tested ELT’s DLC-drivers with it, and they have good compatibility.

Click the button below to download the datasheets and material. You can find more information and our product codes from the presentation. If you have any questions about Dim-to-Warm, please don’t hesitate to contact us.

Download Here

Why Heat Pipe is Better than Traditional Heat Sink?

You will need a heat sink when you use a COB led for your luminaire. The traditional way of transferring the heat away from the light source is to use passive aluminum heat sink. In this post, I introduce another solution for cooling the led: Heat pipe.

Traditional heat sinks are based on the fact that aluminum transfers heat away from the light source. The higher the power of the led is, the more you need aluminum.

This grows the luminaire’s size and makes it more expensive. The bigger size of the luminaire makes logistics costs go up and increases the price for end user even more.

There is another solution for the high power leds without the need for noisy fans etc: Heat pipe.

Heat pipe technology is traditionally being used in computers and for example in satellites. But now it is available in lighting.

Furukawa Heat Pipes (HYC Series)

Furukawa HYC Series uses heat pipe technology to transfer the heat and makes heat sinks more efficient in cooling the LED.

how heat pipe works

How Heat Pipe Works

Heat Pipe’s thermal conductivity is almost 200 times better compared to copper. This allows the heat sink to be a lot smaller than we are used to.

Smaller heat sink reduces the weight of the luminaire dramatically. This reduces the transportation costs as well as the amount of other materials needed.

The heat pipes effectively transfer heat from the heat source throughout the whole heat sink cooling the heat source faster than ever.

Unlike many Chinese manufacturers, Furukawa uses oxyzen-free copper in its heat pipes, which means that their lifetime is over 20 years.

Heat Pipe vs. No Heat Pipe

Heat Pipe vs. No Heat Pipe

Save money and environment with our product

aLED Engine

aLED Light Engine (Furukawa heat pipe + Citizen COB + optics + aLED Driver)

Now I want to introduce you our own aLED Light engine that uses Furukawa heat pipe with Citizen COB. aLED Light Engine produces over 40.000 lm and weights only 1 kg (without driver and optics). And only 3.6kg with optics and driver.

By combining Citizen COB and heat pipe technology, you can build luminaires that:

  • Produce a lot of light
  • Are light in weight and small in size
  • Save environment
  • Are completely recyclable

Heat pipe is very lightweight. You can get a lot of light with a smaller luminaire.

Furukawa heat pipes are compatible with Citizen CLU04x and CLU05x COB leds.

Download an example of different led + heat pipe combinations and datasheets for custom models with screwholes for Citizen COBs.

Download Here

Microwave Sensors: How to Utilize Them in Lighting?

This blog post deals with microwave sensors. Especially how they are used with general lighting components to realize intelligent lighting systems. Some pictures enlighten the possibilities of microwave sensor technology better than hundreds of words.

Microwave Sensors

Microwave motion sensors operate in a different way that e.g. more commonly used passive infrared sensors. MW sensor sends out microwaves and analyzes the echo that comes back to the device.  If the movement changes the echo pattern the sensor will respond and switch the light on.

Microwave sensors have a consistent capability of detecting movement over all temperatures. PIR sensors’ detection sensitiveness might vary depending on the temperature. In addition, infrared sensors are vulnerable to dust and smoke and tend to have a shorter lifespan.

The lifetime of a microwave sensor is around 50.000 hours and our sensors are completely dust- and smoke-proof.

Example of a detection pattern when the sensor is mounted either on a wall or on the ceiling. Detection area can often be precisely set via dipswitches.

Microwave sensors can also detect movement through some non-metal materials such as glass and even thin walls. This gives more options for installing the sensor because it can be located out of sight or inside the luminaire.

Energy-saving In More Ways Than One

In addition to the traditional ON-OFF -control of a luminaire our sensors offer a wider selection of functions. You can also choose between 2-step and 3-step dimming. You can create larger networks of luminaires by utilizing RF communication between sensors to control several luminaires at once.

Some products have built-in daylight sensors, which enables you to fully take advantage of daylight and maintain sufficient light levels during dusk and dawn. This is called daylight harvesting.

Wikipedia states that several studies are implying to energy savings through daylight harvesting being around 20-60%. The greatest savings are achieved in rooms and areas where daylight has a significant impact on the lighting conditions through large windows for example.

In addition to energy savings, using these sensors also prolong the lifetime of your luminaires when luminaires are not on unless the light is actually needed.

Daylight sensor detects the level of ambient light and adjusts artificial light accordingly.

Endless Possibilities to Better Lighting Conditions

Correct lighting conditions make reading and writing more enjoyable, improves safety and can even have a positive effect on health. Where to use these sensors to get the best possible benefit out of them?

Some sensors are stand-alone models and can be connected to the LED driver. Other sensor products already include the driver. This gives you more options when you’re planning your lighting setup.

I have picked a few examples for you just to give you an idea of all the possibilities this kind of intelligent lighting control technology possesses.

Balcony: On/Off — Warehouse: 3-step dimming — Office: Daylight Harvesting

Restaurant: DALI LED Driver — Restroom: 3-step Dimming — Gas Station: Cluster Control & Daylight Harvesting

Conference Room: Cluster control — Underground Parking: 2-step Dimming — Stairwell: RF Wireless Control

As you can see, there are numerous function options and product combinations. To see a more detailed list of all the different types of sensor products in our range, take a look at our website.

To download a presentation on these sensor products, simply click the button below.

Download Here

Why Should You Choose the New aLED Module

We redesigned our aLED-modules based on customer and market feedback. Here is  a brief explanation on what is different compared to previous version. And why I think you should consider using aLED modules.


Figure 1. New aLED Modules with examples of different connector locations.

Better efficacy (159-191 lm/W)

We upgraded the SMD LEDs used in the modules to better suit our customers’ needs. aLED modules now have efficacy from 159 lm/W to 190 lm/W. Efficacy depends on the color temperature and you can see the efficacy by CCT here:

  • 2700K (174 lm/W)
  • 3000K (177 lm/W)
  • 4000K (185 lm/W)
  • 5000K (191 lm/W)

Better placement of LEDs

We have changed the design of our aLED module. LEDs are now placed on the center line of the module so the installation of optics is easier.

aLED modules dimensions have also changed. New modules are now either 279.2 mm or 558.4 mm in length and 20 mm or 40 mm in width. 

Different options for connectors

It is now possible to order aLED modules with connectors either on the frontside or on the backside. Traditionally the connectors have been on the frontside, but these new backside connectors allow you to hide the wires behind the module and inside the profile.

For longer luminaires, there is a possibility to use backline, so you won’t need long wires. Short wires to connect multiple modules together will be enough (figure 2).

Figure 2. a) How to connect modules without back line option. b) How to utilize the back line option of the aLED modules.

Long lifetime

Thanks to the upgraded LED, the lifetime of aLED modules has also increased. You can see the lifetime prediction below. But to be brief: at maximum TC temperature (85°C) the lifetime (L70B50) is over 100.000 hours (figure 3).

Fikure 3. The lifetime of aLED Module (L70B50)

Friendly to environment

On top of high efficacy and the possibility to save energy, aLED modules are also recyclable. You can recycle all parts of module, even the PCB.

In addition to all these changes aLED modules prices have also dropped to more competitive level.

You can find the technical details of 4000K modules from the table below. You can download the datasheets of these new modules by clicking here.

Product Code Color Temperature (CCT) Color Rendering (Ra) Luminous Flux (lm) Forward Current (mA) Voltage (V) Power (W) Efficacy (lm/W) Length (mm) Width (mm)
CALOSNU0405 4000 80 1182 600 11.6 7.0 170 279.2 20
CALOSNU0410 4000 80 1224 600 11.0 6.6 185 279.2 20
CALOLNU0805 4000 80 2363 600 23.2 13.9 170 558.4 20
CALOLNU0810 4000 80 2448 600 22.1 13.3 185 558.4 20
CALOLHU1610 4000 80 4895 600 44.1 26.5 185 558.4 40
CALOSND0405 4000 80 1182 600 11.6 7.0 170 279.2 20
CALOSND0410 4000 80 1224 600 11.0 6.6 185 279.2 20
CALOLND0805 4000 80 2363 600 23.2 13.9 170 558.4 20
CALOLND0810 4000 80 2448 600 22.1 13.3 185 558.4 20
CALOLHD1610 4000 80 4895 600 44.1 26.5 185 558.4 40


Download Datasheets


In addition to these new models, all our previous module models are also still available.

How to Connect LED Modules into AC Network

In my earlier post I went through the procedure of how to physically connect a single LED component into an AC network. The connection was made between COB LED and the LED driver. When connecting LED modules (LED diodes assembled on the PCB board) you do it pretty much the same way with slight differences.

Connecting an SMD LED module into the AC network

As with a COB LED component, you will need a suitable driver for your module (see: how to choose a constant current LED driver).  You connect the positive terminals and the negative terminals of the LED driver and the LED module together to create a closed electrical circuit.

The difference to connecting a single LED component is that you may have to connect several LED modules into the same LED driver. In such case, you have to use series connection. This means that you still have to create a closed electrical circuit formed by the LED driver and these LED modules on the secondary side. You arrange the primary side like you would with single LED components. On the secondary size you connect the positive terminal of the first LED module (leftmost module in Figure 1) into the positive terminal of the LED driver. Then you connect the negative terminal of the last module (rightmost module in Figure 1) to the negative terminal of the LED driver. See Figure 1 below that shows all connections between the components.

Figure 1. Connection of LED modules into AC network through the driver.

How do you make other connections? Series connection means that you always connect the negative terminal of the previous array to the positive terminal of the following array in the chain. See again Figure 1. The output voltage of your LED driver defines how many LED modules you can drive with one driver. In case of Figure 1, one LED driver drives three LED modules. If voltage over LED module is for example 12V, the output voltage of the LED driver should exceed 36V. In the real world, you have to take into account tolerances. So in this case, 40V can be used as target for the driver maximum output voltage.

In the same way, you can connect multiple COB LEDs in series. This may be the case when you need vast amount of light.

How to actually do it?

As for physical connections of SMD LED modules, there are four options:

  1. PCB terminal block connectors
  2. Soldering
  3. Wire-to-board connectors
  4. Board-to-board connectors

PCB terminal block connectors are quite popular. They are soldered on the PCB board in the reflow process (in reflow oven) after the assembly process. You push the wires into those PCB terminal blocks in the same way as you would push the wires into the push-in terminals of solderless connectors in the single COB case.

Figure 2. PCB terminal block connector (2-pole)

Soldering is an option, if there are separate soldering pads reserved on the PCB to solder the wire(s) with tin. Soldering is usually a more cost effective option.

The numbers 3 and 4 are the special cases when you wish to interconnect two modules with each other. I’ll skip them for now and save them for later post.

If you’re interested in aLED’s new, improved LED modules, read more over here.

Feel free to drop a comment if you have questions on this topic.

How to Connect a Single LED Component into AC Network

I have two blog posts for you focused on how you connect COB LED components into the electrical network. I mean, when you have either a single COB LED or an LED module based on SMD LED components assembled on a PCB board.

Compared to traditional lighting, connecting LEDs to the electrical network is a whole new world. LEDs need direct current (DC) to light them, alternating current (AC) will not work. There are also AC modules available but those are not covered here.

In this post I will concentrate on connecting single COB LEDs. In case you are interested in connecting LED modules, I will write about that in my next post.

LED driver

You will need an LED driver, which is actually an AC/DC converter. It converts the AC voltage/current of the electrical network into the suitable DC voltage/current needed by the LED component. You will find the requirements of the LED from a datasheet provided by the manufacturer. If you need help in choosing a driver, you can read our guide.

Figure 1. Example of an AC/DC converter, LED driver. This one is from ELT with dipswitches, which means that you can choose the driving current.

Connecting COB LED into the AC network

In case of COB, you will have to create a closed electrical circuit so that the electrical current can flow through the LED component. A COB LED is basically a diode in its electrical nature: the current can flow only in a forward mode. This means that you must connect the positive (+) solder pad of the COB LED into the positive terminal of the LED driver. In the same way, you connect the negative (-) solder pad of the COB LED into the negative terminal of the LED driver. See the Figure 2 below.


This way, you create the closed electrical circuit that is needed to feed current through the LED so that it gives light. This closed electrical circuit formed by the LED driver and the COB LED is called the secondary side of the LED driver. LED driver feeds the power and current into the closed electrical circuit, and thus through COB LED, on the secondary side.


Figure 2. COB-AC Network


On the primary side, the LED driver gets electrical power from electrical network, AC network. The terminals of the LED driver on the primary side are called line and neutral. They are connected into the line and neutral connections of the AC network. If you have an LED driver with cables, they are usually blue (neutral) and brown (line). Some drivers also have a ground terminal, which is usually connected to the luminaire body with grounding wire. However, the closed electrical circuit is needed also on the primary side; between the network and the driver.

Usually, you will need to use some kind of terminal block to connect the driver into the electrical network on the primary side.

Picture of a terminal block

Figure 3. The example of terminal block to connect the LED driver into the electrical network.

Two options

Finally, as for physically connecting a COB LED into the LED driver, you have two ways to do it:

  1. solder the wires on the solder pads of the COB
  2. use solderless connectors.

In the first method, you manually solder the wire by using soldering iron with high temperature that melts the soldering material such as tin. After cooling, there is a joint between the wire and the COB solder pad. You need two wires, one for plus and one for minus solder pad.

In the second method, you use a solderless connector.

Figure 4. The solderless connector.

The solderless connector does the same effect as the soldered wire. You need the electrical connection also in this method, but you won’t need to solder the wire by melting tin. You just push the wire into the push-in terminals of the connector. Again, positive to positive and negative to negative terminal. They are marked on the connector. Basically these push-in terminals work with a combination of metal plates and springs that then make the connection to the solder pad of the COB LED.

The difference between these methods is, that unlike with soldered joints, in the solderless connector method the springs may loosen a bit over time and loss of contact may occur. Solderless connectors are generally thought to be more expensive than manual soldering.  

In my next post I will go through the steps for connecting LED modules.