In this article we will show you the main characteristics of SMD (Surface Mounted Device) type LEDs and the various types of existing models. We will provide you a series of useful application tips to be able to get the best from the different models existing today. This guide will not only provide information on the most commercial and widespread models of SMD chips, but also takes into consideration special models of SMD LED sources that we present to the public here and which constitute an innovation capable of creating new lighting effects and solving problems up to now difficult or impossible to solve.
SMD type LEDs are light sources that have the characteristic of being installed in circuits directly mounted on an electronic board. These circuits are perforated to allow the passage of the electrodes, whose welding is carried out on the lower face of the base. These are components where the electrodes do not protrude downwards, but come out from the sides of the chip. They are characterized by their flat shape: the lower part is welded directly on the electronic board, while the electrical connections are on the side. In this way it is possible to use printed circuits on an insulating base of reduced thickness and to carry out the micro-welding with automated machinery. This type of LED looks like a tiny box with one face from which the light is emitted, the opposite face which acts as a support base, while the remaining side faces are equipped with anode and cathode. In the past they have been used in miniature circuits, such as those of mobile phones, thanks to an ever higher luminous efficiency. Today they are widely used in the production of LED luminaires for general lighting. This type of LED normally has a light output of 120 degrees and is typically used, for example, in the production of LED strips.
In essence, it is a really interesting family of LED diodes since today it finds a great application both in the production of LED strips and in the production of LED luminaires and especially where high efficiency and the achievement of very high lumens are required together with a control of the very precise light distribution (LED luminaires for public, industrial, cultivation lighting, etc.). The SMDs are also a family of LED sources that allow the achievement of high standards of reliability and durability thanks to the possibility of fragmenting the power of the luminaire into a plurality of diodes to be powered with voltage generally in the order of milliamps (mA) (for an in-depth study on the thermal management of SMD LEDs in relation to COB LEDs (we invite you to read this dedicated article).
Voltage(V) 2110 2,1 1,0 8-12 2.8-3.3 2216 2,2 1,6 6,5-7 2.8-3.3 2735 2,7 3,5 4-8 2.8-3.3 2835 2,8 3,5 8-14 2.8-3.3 3014 3,0 1,4 10-12 2.8-3.3 3020 3,0 2,0 10-12 2.8-3.3 3030 3,0 3,0 61-85 2.8-3.3 3528 3,5 2,8 6-7,5 2.8-3.3 5050 5,0 5,0 16-24 2.8-3.3 5630 5,6 3,0 54-56 2.8-3.3 5730 5,7 3,0 25-28 2.8-3.3
The models of SMD LED sources mentioned above all have peculiar characteristics that justify their existence. As is intuitive from reading the table, the name of each model corresponds to the size of the chip expressed in millimeters. Here we will explore the most popular models, as well as the most performing and professional ones that can be effectively used in general lighting.
SMD 3528 LED diodes represent the older models and are characterized by a not particularly high light output. The 3528 diodes are therefore mostly used in decorative lighting and are characterized by their low cost. On DOMAGIC you will find the 3528 4.8W/m and 3528 9.6W/m LED strips.SMD LED 2835
The SMD 2835 diodes, on the other hand, are more recent and have enjoyed an excellent diffusion on the market thanks to their greater efficiency and the possibility of making LED strips with a good density of diodes. This last aspect is fundamental when you want to create a luminous effect of continuous light and avoid the unsightly “dots” or “dotted” effect, which is inevitable where SMD diode models characterized by a diode density of less than 120 per meter are preferred. DOMAGIC presents various models of SMD 2835 diodes with various powers: 14.4W/m (120 LED/m), 17.3W/m (168 LED/m) and 20.2W/m (240 LED/m) with high color render (CRI>95).
SMD 5050 LEDs are among the first diodes capable of delivering adequate power for general lighting needs. The LED strips that mount them, however, have the drawback of having a low number of diodes per meter (generally 30 or 60 per meter) and this inevitably leads to the unsightly “dotted” or “dots” effect due to the excessive separation between diode and diode. The powers available generally range from 9.6W/m to 28W/m.
SMD 5630 and 5730 diodes have in common their recent development and great brightness. These are LED diodes suitable for use where high lumens are required. DOMAGIC has long been available the 26.8W/m (120 LED/m) 5730 LED strip capable of expressing 2,660 lumens per meter, today surpassed by the clearly superior performance of the 21.6W/m 2835 LED strip with a density of even greater LED diodes (as many as 168 LEDs/m) and an extraordinary level of efficiency higher than 146lm/W (with a flux at 4000K Ra>80 equal to 3150 lumens per meter).
The SMD 2110 LED diodes are among he most recent and in addition to the excellent brightness they have the particularity of being able to be mounted very close together almost eliminating the space between diode and diode. The result obtainable from these strips is a beautiful continuous light effect even when mounted on aluminum profiles with transparent or extra transparent refractor. This SMD LED model allows you to even reach up to 700 diodes per meter!
As seen, each SMD chip model has its own characteristics and peculiarities that require and justify its use in certain applications and this based on two fundamental factors which are:
performance: understood as luminous efficiency, power, useful life, type of step (ie how many millimeters the strip can be cut), width of the LED strip;
light effect: which can vary depending on the density of LED diodes per meter, the supply voltage of the strip, the quality of the diode in terms of color rendering as well as the quality of the color temperature.
do I need a decorative LED source or for general and functional lighting?
In the first case, if the need is to have a decorative LED strip, the choice can fall on SMD 3528 LED diodes, which as mentioned are characterized by the possibility of having limited powers (starting from 4.8W/m ). However, if the application requires good light homogeneity, it will be necessary to choose intermediate powers such as 9.6W/m so as to have at least 120 diodes per meter (4.8W/m are generally distributed on strips of 60 diodes per meter), possibly from combine with dimmer to adjust the intensity of the emitted flux if it is excessive.
The aspect to consider is that the characteristic energy efficiency of the SMD 3528 LED diode is not the highest in the face of a rather low purchase cost. Also for this aspect it is worth comparing with the characteristic elements of the concrete application: if the strip is destined to remain lit on average for a short time a day it will be worthwhile to buy the 3528 model since the aspect of energy efficiency passes into second floor compared to the lower purchase cost. If, on the other hand, the application requires medium-intensive uses, it is advisable to refer to the SMD 2835 LED model.
As for the 2835 model, it is an SMD chip which in terms of cost quality turns out to be one of the best ever. The LED strips that mount it can be used both for a decorative function and for a real lighting function. This is because it is a chip that has known a great favor on the market and is therefore available at low powers (tipically 4.3W/m, 4.8W/m, 6W/m, 7.2W/m, 8.6W/m, 9.6W/m and 10.1W/m) as well as powers suitable for lighting entire rooms (14.4W/m, 17.3W/m, 20.2W/m). Furthermore, starting from 14.4W/m the strips have 120 LEDs per meter, to go to 168 LEDs per meter for the 17.3W and 196 LEDs per meter for the 20.2W (in this case arranged in two parallel rows). On DOMAGIC we offer high quality LED strips with SMD 2835 diodes, capable of producing high lumen light beams with excellent color rendering (from CRI>85 up to CRI>95). In the opinion of the writer, this is a choice that makes the most of in applications that require a high quality, homogeneous and powerful general lighting solution (and therefore with powers starting from 14.4W/m).
From the above it appears that, in general, we tend to recommend strips with SMD 2835 LEDs instead of the 5050s as the former, in addition to guaranteeing optimized heat distribution thanks to the greater number of diodes per meter, allow the creation of truly homogeneous continuous light. The second, as mentioned above, produce the dotted effect which in most cases turns out to be unsightly. Click on the link for more information on the comparison between 2835 and 5050 chips.
As for the SMD 5630 and 5730 models, these are sources capable of emitting high or very high lumens, particularly suitable for professional lighting and for applications in which opal screens are used (capable of significantly reducing the actual luminous flux emitted. from the luminaire) or to minimize the dispersion typical of applications that require indirect light (so-called soft light). In these cases, thanks to these models of SMD LED diodes, it is possible to obtain large lumens with less energy absorption and therefore effectively illuminate, for example, large areas, very high rooms or create lines of light hidden in plasterboard veils. If it were then necessary to create the lighting of offices or similar workplaces, thanks to these sources it is normally possible to reach the levels of illumination prescribed by the regulations in force, perhaps in combination with anti-glare microprismatic screens able to manage and control the emission. diffuse typical of the strips (120°) and thus minimize the risk of glare (UGR<19).
Particularly bright and qualitative strips are those that we offer in the version with 4000K light tones, very high chromatic fidelity (CRI>90) and very high lumens (150 lumen/W) and which are fitted with the SMD 3030 diode. These LED strips have 80 diodes SMD by the meter of the Nichia brand, one of the best producers of SMD sources in the world, and are characterized by a truly exceptional purity of light. These are professional LED strips capable of ensuring maximum reliability even in intensive applications.
As for the brand new SMD 2110 LEDs, it should be underlined here that through this technology it is possible to create continuous lines of perfectly homogeneous light even in the presence of transparent or ultra-transparent refractors, even in the total absence of refractor. This is because the very high density of the number of diodes prevents the human eye from viewing the hundreds of point sources individually, giving way to the vision of a perfectly homogeneous strip. Also in this case, since the luminous efficiency is comparable to strips with SMD 2835 diodes, it is advisable to purchase it for professional use where the lighting effect, unique and exclusive, is the prevailing need.
Fundamental in the choice is then the verification of the size of the LED strip (it generally goes from 8mm in width to 15mm of the LED strips with double row of SMD diodes) which will be considered in the choice of the aluminum profile in which to lay the strips themselves. last element that must never be missing to allow the best heat dissipation and maximize the useful life of the SMD LED sources and which it is good to check the dissipating capacity in terms of Watt (on DOMAGIC the data is specified for each aluminum profile or linear system). In addition to the size, the pitch of the strips also plays a fundamental role: for example our 4.8W/m strip with 3528 diodes can be cut every 100mm, the 20.2W/m can be cut every 71mm, while the 5730 strip with 26.8W/m can be cut every 50mm.
As for the power supply voltage, whatever the chosen strip, it is highly inadvisable to purchase them with a 12V/DC power supply voltage and this to avoid voltage drops. In general, if you exceed 5 meters in length or if there are no particular problems, it is always good to have strips powered at 24V/DC and this to ensure the best uniformity of voltage and therefore of brightness.Representation of the color rendering level on the CIE color plates
Always in general, whatever the choice of SMD chip model, it is always good to check that the strips are of quality, that is, they are reliable and with high quality of light. Reliability essentially depends on the components of which the strip is made and, above all, on the brand and model of the diode.
The light quality, on the other hand, is expressed in the quality of the light tone (warm, neutral or cold light) and in the ability of the light to faithfully reproduce the colors of the environments and of the things and people they contain and which is measured from 0 to 100: CRI>95 means that the source is capable of reproducing colors with a practically maximum level of accuracy and fidelity, CRI>98 or Full Spectrum (FS) means maximum levels of chromatic fidelity. These are aspects of fundamental importance which, together with all the above, justify the price differences that can easily be observed by comparing the wide range of LED products on the market today.CRI>80, CRI>95 and CRI>98 (FS) in comparison
DOMAGIC‘s philosophy is to offer high-performance lighting solutions, able to respond excellently to any need, as we want to allow anyone to equip themselves with the best possible technology without compromising on quality. In addition to the available catalog, we are able to create customized SMD LED sources in every aspect. We are often chosen by companies, as well as by individuals, and this testifies to the trust our customers place in us and in our LED solutions! Contact us to find out more or visit our online shop.
You can learn more about the difference between COB diodes and SMD diodes by clicking on this link.
Comparison of SMD LED Types and Application Tips