SMD 3528 - specification and description
LEDs are now actively used in a variety of industries. Popular is a crystal type SMD 3528. Despite the fact that during its existence a huge number of more modern devices have appeared, the model is relevant due to its reliability, low cost and good technical characteristics. On their basis are created fixtures and LED strips. Let's consider the features and parameters of SMD 3528.
Description and features of application
Dimensions of SMD 3528 LEDs are 3.5 mm by 2.8 mm. The height of the crystal is 1.4 mm. On each side there are two contacts through which current flows. Only transparent lenses are used in the manufacturing process to ensure quality light transmission.
On the cathode side, you can see a special cut on the housing. This cut is sometimes called a key. The entire surface of the product is covered with phosphor, which performs, in addition to light transmission, a protective function.
SMD 3528 refers to the category of small super-bright LEDequipped with a housing for mounting on different surfaces. The crystal itself is made from a mixture of gallium nitride and indium nitride. The result is a special structure that creates bright radiation. It contains aluminum-, gallium-, and indium-based phosphide.
The numbers in the model designation tell you the size of the product, so it's not hard to imagine installing the device in one area or another.
You can find a particular model on the market that is labeled SMD 5050. It is a prefabricated design consisting of 3 standard 3528 crystals enclosed in one housing, which gives an increase in power. Products have a very low level of crystal degradation, which significantly prolongs the life of the product. The LEDs feel great even at temperatures above 100 degrees Celsius.
Relatively low cost and ease of installation has allowed the use of LEDs of this type in many areas of life. They are most commonly seen as the main components of LED strips, as well as various indicators on appliances. They can be seen in backlighting systems, signage, and other applications that require a small source of bright light.
On the basis of LED 3528 was created a lot of modern devices with three-color RGB-backlights and crystals with improved light output.
Parameters and characteristics of species
SMD 3528 LEDs are made based on InGaN (gallium nitride, indium nitride) and AlGaInP (aluminum, gallium, indium phosphate). Most crystals of this type have a color rendering index of 60-80 Ra and a color temperature range of 3000-7500 K. This is higher than the larger SMD 5328. The luminous flux is generated from 5 to 11 Lm.
The light output is 40 Lm/W, which makes these LEDs extremely efficient for lighting small areas. No heat sink is provided as the crystals handle the elevated temperatures quite well. The scattering angle is 90 degrees and the area of light emission is 4-5 mm.
The most comfortable temperatures are considered to be from -40 to +85. And if with exceeding the upper limit usually no problems do not arise, too low temperatures can lead to the failure of the crystal.
It is worth noting that the final brightness of the light very much depends on the temperature. Operation at temperatures from +60 can reduce brightness by 10%, and exceeding the 80% limit will cause a decrease in brightness by 25%. This is one reason why semiconductors need cooling.
During manufacturing, products are binned - a binary code is installed that determines the color, temperature, and coordinates of the light. Some manufacturers accompany their products with special chromaticity charts.
During operation, the power dissipated is 100 mW, with a direct voltage of about 3 V. The devices operate with a current not exceeding 25 A.
Listed below are technical specifications of SMD 3528 LEDs with different color ranges. For convenience, there are graphs of operating values.
Red LED
Red LED specifications:
Volt-ampere characteristics of red LEDs:
Yellow LED
Yellow LED specifications:
Volt-ampere characteristics of yellow LEDs:
Green
Specifications green LED:
Volt-ampere characteristics of green LEDs:
Blue
Blue LED specifications:
Volt-ampere characteristic of blue diodes:
White
White LED specifications:
Volt-ampere characteristic of white diodes:
White LEDs are on the market in two varieties:
- cold light;
- warm light.
The difference lies in the composition of the emission spectrum.
Pros and cons
SMD 3528 diodes have a number of specific features that are recommended to consider when choosing. There are both positive and negative aspects.
The advantages of diodes can include:
- economical power consumption;
- relatively low cost;
- flicker or pulsation does not occur during operation;
- minimal heating.
Disadvantages:
- low power, especially in comparison with later developments;
- inevitable crystal degradation with loss of necessary properties;
- the possibility of manufacturing defects, which are difficult to assess in advance.
We advise to watch video: TEST/COMPARISON OF SMD DIODE STRIPS 3528, 5050, 5630, 5730. ALIEXPRESS.
How to choose correctly and not to get a fake
There are quite a few LED 3528 on the market from well-known companies, including such giants as LG, Philips and Samsung. But this has not secured the product from a huge number of fakes with completely different characteristics. To make production cheaper, unscrupulous companies often resort to artificial reduction of crystals, reducing power and performance parameters.
Without experience, it's difficult to spot a fake.. But there are a number of features by which a low-quality product is identified:
- The base. Fakes are often created on aluminum frames, while the original diodes use only copper for better thermal conductivity. A comparison of appearance as well as weight will help determine the material. Aluminum is lighter (estimating the weight of a small diode without special scales is almost impossible, so it is better to compare large batches of products at once).
- The makers of fake diodes often do not specify the number of hours of operation before the flux is reduced to 80%, limiting the total lifetime.
- Cost. LED 3528 SMD are considered quite affordable. However, their price cannot be lower than some set value. Fake suppliers can supply equipment at extremely low prices, but also the quality of the diodes will be very low.
Wiring rules
The marker for determining the correct connection is the cut of the angle shown in the figure below.
For reliability, it is better to use a series connection with the use of current-limiting resistors. Below is a diagram of such connection.
The ratio of the supply voltage to the voltage drop minus one will show what is the optimum number of diodes you can include in the mains.
To select a resistor use the formula for calculating resistance through voltage and current.
N stands for the number of LEDs connected in series. The rated current Ipr for the 3528 is about 25 mA. Since the calculations may not add up to an integer number, it is common to take a resistor rounded up.
