More recently, LEDs were used mainly as indicators for turning on / off various electronic equipment. However, modern technologies for the production of radio and electrical components are moving forward by leaps and bounds. Now such devices are used in a wide variety of industries. The choice is very wide both in the number of manufacturers and in the variety of modifications. Due to its high technical characteristics, 2835 LEDs are most widely used by numerous manufacturers of energy-saving lamps for various purposes.
Marking, description and design features
The four-digit digital index in the marking indicates the overall dimensions of the LED chip. For the device of the form factor 2835 they are: length - 2.8 mm, width - 3.5 mm, thickness - 0.8 mm.
Design and technological features:
- The case is made of special heat-resistant plastic and is attached to an aluminum heat-dissipating substrate (0.25 mm thick).
- The increased radiation area (compared with analogues of other series, for example, 3528) is 6.9 mm², which is more than 70% of the total overall chip area.
- Increased soldering contacts, which contributes to the additional removal of excess heat.
According to both Russian and international classification according to their characteristics, SMD 2835 LEDs belong to the group of high-efficiency devices with increased brightness of medium power and are designed for surface mounting.
Operating voltage and rated current
Among the electrical characteristics, two main ones can be distinguished that affect the choice of a power source:
- Operating voltage (the value of the voltage drop on the LED itself) is usually indicated in the index of the device and is the average value between the minimum and maximum permissible value.
- The rated current flowing through the product, which is necessary for proper operation and to ensure the rest of the parameters declared by the manufacturer.
According to the current-voltage characteristics, SMD 2835 LEDs now produce:
- with operating voltage: 3, 6 and 9 V;
- with rated current from 60 to 150 mA.
The choice of a particular product depends on the area of its application.
On a note! For long-term and uninterrupted operation of the LED, the appropriate driver must be used.
Luminous efficiency, efficiency and power
These are three very important and interconnected technical characteristics of the 2835 LED. Light output characterizes the amount of light flux emitted by one device. For products 2835, depending on the specific modification, its value is in a wide range from 24-29 lm (for varieties with an operating voltage of 3 V and a rated current of 60 mA) to 130-140 lm (for models designed to work from 6- 9 V and rated current 100-150 mA).
The efficiency of the device is the ratio of the luminous flux to its power consumption. The 2835 Series is a high performance device. The value of this indicator is in the range from 120 to 170 lm / W. It is for this indicator that you can compare lighting lamps made using various technologies (incandescent, fluorescent, halogen and LED) with each other.
The power consumption of the 2835 LEDs currently being manufactured is 0.2, 0.5, or 1.0 watts.
Glow temperature and scattering angle
Although all 2835 LEDs emit white light, the color perception of different versions is different. This parameter is called the glow temperature (or color temperature) and is expressed in degrees Kelvin. According to this indicator, all devices are conventionally divided into three main groups:
- 2700-3500 K - warm white (most reminiscent of light from a conventional incandescent lamp);
- 3500-5000 K - neutral white (or daily);
- 5000-6500 K - cold white (used mainly for the manufacture of car headlights and flashlights, as well as for street lighting).
2835 form factor products are available in all three color temperature groups.
Another important characteristic of the 2835 LED is the scattering angle. This value characterizes the angle of propagation of light, within which the intensity of the light flux will be at least ½ of a similar indicator on the axis of the crystal. For LEDs in this series, this figure is 120⁰.
Advantages and scope
2835 LEDs have a number of undoubted advantages:
- good energy-saving performance with a fairly small power;
- small dimensions;
- a wide selection of various modifications;
- wide angle of dispersion;
- a wide range of operating temperatures (from -40 ° C to + 105 ° C);
- low ripple glow;
- high resistance to mechanical stress and vibration;
- long service life.
All these advantages and high technical indicators have predetermined the widespread use of LEDs of this series in a variety of lighting devices: lamps, light panels of various sizes, LED tubes and so on.
Characteristics of LEDs 5730 and 2835 in comparison
Historically, LEDs of size 5730 appeared on the market much earlier than 2835. Therefore, initially they were rather widely used in the production of energy-saving lamps. Now 2835 LEDs are replacing the 5730 format. Let's take for comparison devices from the well-known in our country and well-established Chinese manufacturer Honglitronic. Comparing devices of different form factors of the same power and glow range, we conclude that the technical characteristics (both operational and maximum permissible) are almost identical.
The difference lies only in the design features: the 5730 case significantly exceeds 2835 both in area and in thickness.
And this, in turn, provides the former with higher strength and vibration resistance. In addition, the “elder brother” has a protective lens glued on top of the light-emitting element, which significantly increases moisture resistance. Therefore, it is 5730 that is often used in the manufacture of automotive navigation lights, direction indicators or brake lights.
What to look for before buying
LEDs of the 2835 series are widely used not only by manufacturers of industrial lighting devices, but also by numerous amateurs to make exclusive lamps with their own hands (or, for example, to repair failed LED household lamps). Of course, if you purchase such devices in highly specialized stores, the sales assistant will tell you all the necessary information. However, ordering such products over the Internet greatly facilitates this process and also provides the greatest choice in price, manufacturers and variety of models.
Before buying, you must carefully study all the characteristics of the 2835 LED and familiarize yourself with the principle of marking. Each manufacturer has its own. Take for example the LED of the well-known and popular in Russia American company Cree JE2835WTA0G727E:
- J - series for surface mounting;
- E - power 0.5 W (K - 1.0 W);
- 2835 - geometric dimensions of the chip;
- WT - color is white;
- A0 - operating voltage 3 V (B0 - 9 V);
- G7 - the amount of light flux 63-66 lm;
- 27E - light temperature 2700 K.
Having carefully read the detailed information on the manufacturer's website, you can choose and purchase exactly the device that you need.