作者：Blade

How to make high quality LED chips (2)

Except individual LED chips, LED Lights packaging and LED power supply can impact significant influence on their capacities, brightness and color. We defined them as internal factors. External factors are mainly from circuits and other electronic components. Since working temperatures, current, circuit construction, voltage peak can also affect the performance of LED chips. Proper circuit design and assembly is the key to protect the LEDs and ensure their performance. During the packaging process, even different assemblers with different working experience will cause the non-uniformity.

 Except individual LED chips, LED packaging and LED power supply can impact significant influence on their capacities, brightness and color.

With the rapid development of LED demand, the global-oriented LED chip suppliers and packaging factories are booming simultaneously. Unfortunately, the over-booming trend made many manufacturers choose to use low quality LED chips to reduce cost. Besides, their LED packaging designers and engineers are usually lacking of working experience. Most OEM producers have no capability to establish their own LED chips sections. Replying on other LED chip suppliers is their single solution. Experienced producers know how to choose right suppliers and also conduct a series of testing for LED packaging and circuit structure.

 

In order to eliminate the injustice during the testing, many companies chose to employ a third party to test the quality of LED street light chips. In the period of testing, randomly chosen LED chips will be gathered together into some specific testing rooms. These LED chips will be continuously working for several weeks in the harsh conditions, including pressure test, temperature test, fixed/flexible voltage test, fixed/flexible current test, etc. A large amount of data should be recorded before and after the testing. The three major parameters of LED: light intensity, color, potential drop should keep in record during the entire testing process. Only high quality LED chips can survive from it.

 

Accelerated life cycle testing is a key point to avoid failure in special applications. This test can help eliminating those LED chips which has an estimated service life more than 100000 hours but will be failed after 1000 hours work. This happens often. The light intensity of low quality LED chips (or high quality LED chips with unreasonable assembling) will drop dramatically after 1000 hours work. In fact, low quality LED tubes chips using higher driving current are more brightness than high quality LED chips in the early stage of service. However, continuously working in high temperature may cause huge damages to them.


How to make high quality LED chips (1)

Most LED lighting designers believe that all LED chips have same quality. However, there are hundreds of thousands of LED chip providers or LED chip manufacturers. Asian LED Lights manufacturers can produce the cheapest LED chips all around the world. But, to buyers’ astonishment, only very few of them can actually make high quality LED chips. Low level LED chips can only be competent in small lamp market. But in other application area, in which LED products should be used under severe environment (expressway, military/aviation, other industry), high quality LED chips are necessary.

 Most LED lighting designers believe that all LED chips have same quality. However, there are hundreds of thousands of LED chip providers or LED chip manufacturers.

For new comers in LED industry, how to judge the quality of LED products became one of the must-to-be-learned subjects. In fact, choosing high quality LED chips is the first step. Currently, the internationally recognized best LED chip manufacturer is CREE. Chips made by CREE have a common property of high lighting efficiency. Compare with other LED chips with the same power consumption, like Epistar, SAMSUMG, CREE chips will have more than 5%-10% luminous flux. And also, CREE chips have less light attenuation, which means, the actual service life of their chips is longer than the estimated 50000 hours.

 

If taking chip materials and manufacturing process into account, the most advanced wafer fabrication process must be the essential point. A 2-inch wafer can be cut into more than 6000 LED chips. Using one wafer, a good manufacturer can limited the differences of chips within a very slight region in almost every aspect (chip color, brightness, voltage drop). The differences can only be generated during the packaging process. Low quality LED chips will have huge differences in properties during the chip-cutting process, not to mention the packaging process. Thus LED chips generated by small factories are kind of mixtures without any classifications.

 

Best LED chip manufacturers not only produce high quality LED chips, but also perform classified packaging according to basic LED chip parameters: color, brightness, potential drop, and optic angle. A good LED street light chip suppliers will provide their customers with unified products (with much similar basic parameters).

 

In application area which high quality chips were required, like boundary lights on the airport runway, must reach FAA level certificate. In order to avoid significant accidents, mix-packaged products with much worse uniformity cannot be used.


Which part of the LED lighting industry are making money

From the current market trend, the price war has begun. In particular, after the production of LED lighting and famous Zhongshan large-scale penetration of LED lighting, the competition becomes more intense. Low price record has been renewed. We can only rely on the number of spell profits. As far as I know, the higher corporate profits only have few products lines. But more products within a single series, the quality of the high-end line, mainly for foreign markets.

How is the profit for LED Lights foreign trade?

Current of the lamp price of foreign markets decline, for example, 18W LED fluorescent tube in early is 240-280yuan/piece, and now has dropped to  210-230yuan/piece. European market is relatively better, but Africa and Asia is relatively low. Such difference has created various led lighting industry business development ideas are different, others insist that the route of the high price of higher quality, some choose a low price route.

Which kind of light is more expensive?

Now the most expensive products are the demanded products such as led lighting industry fluorescent lamp, LED bulb lamp, LED spotlight. Because the using amount of these lamps are huge, an office space raging from several thousand to as many as tens of thousands of 10 hours a day. According to the lights count, all-day power consumption is still very alarming.  Like LED lamps for light lamps, LED interior lighting home light market has not to the extent of large-scale outbreak. First, this lamp usage as LED fluorescent tube, the second is the high price of the products. Another is the LED glare problem. The above problems have constrained its growth rate, and large-scale replacement still need time.

If you want to make lighting foreign trade, where the technology should pay attention to?

A lot of led lighting industry wanted to foreign markets, foreign markets, particularly stringent requirements on energy saving and environmental protection, while the LED is the best alternative for energy saving and environmental protection. Many companies for short-term profits. Do everything possible to save material costs, this resulted in the samples and mass production of great hair.

Analysis for low power LED lighting industry

LED lighting technique can be divided into three levels according to the power consumption: low power LED lamps (smaller than or equal to 20W); mid power LED lamps (20W – 50W); high power LED lamps (larger than 50W).  In this article, we will discuss about low power LED lamps.

 In 2010, the selling of global low power LED lamps was around 8.9 billion dollars.

In 2010, the selling of global low power LED lamps was around 8.9 billion dollars. Experts estimated that from 2010 to 2015, the CAGR of low power LED lamps will be 39%. Low power LED lighting industry has a large potential.

 

MR11/16 lamps are low power lamps. Before the emergence of LED Lights, this area was dominated by halogens. A typical design is: 12DC / 24DC after transformers. The equivalent LED lighting technique still need transformers to convert AC to DC. Since they are more vulnerable to the variations of input voltage, transformers used on halogens are not competent. Currently the most commonly used transformer for MR16 LED lamps is high frequency electronic transformer. At present, the small LED market was mainly occupied by these two types of lamps. Both of them have advantages and disadvantages: LEDs have higher light efficiency while halogens are cheaper. 4W LED equivalent to 20W halogen.

 

The biggest challenge for LED MR11/16 lights is lacking of an identical standard, including cover, project, power factor and other electronic parameters. Different low power LED lighting manufacturers may probably have their own standards as a result of immature development. There will be no quick solution for this problem. Manufacturers should recognize the importance of a sustainable industrial development. And government also need to continuously issue support policies.

 

A new solution can embed transformers within LED drivers. As mentioned before, transformers for LED lighting products are much complex than halogens. Typically used solution is non-isolated PFC, which has been removed directly from transformers into drivers. Not only had the entire production process been improved (dramatically reduce cost), but also had the installation been simplified. The new non-isolated PFC drivers are more suitable for small sized PCB used in MR covers. PFC replaced all capacitors with transistors, saving a lot of space. It can meet the requirement of PF and THD only though certain outside components. They have a power factor as much as 80%.

 

Intelligent LED lighting systems in the underground parking lot

Intelligent LED lighting systems using in underground parking lots is a complex combination of advanced digital technique, electronic sensors, wireless technology, signal sampling, central control, LED displays and LED Lights products. It is a brand new intelligent lighting system which can provide sufficient brightness according to the position of carports. The central system will “judge” by itself at what time to switch on lamps. Electronic sensors were installed at some points in advance, covering the enter region. When sensing cars, sensors will trigger adjacent lamps to provide light for them. At the rest of time, these lamps remain in the condition of dormancy. This kind of design can dramatically reduce the energy consumption. Meanwhile, light intensity sensors installed at every carport can automatically adjust lamps for this carport by “judging the nearby brightness”. Within the entire intelligent lighting system, LED technique is just a small but very important part. In order to fully realize the green concept, designers decided to use the most environmental friendly lighting technique at the moment: LED.

 Intelligent LED lighting systems using in underground parking lots is a complex combination of advanced digital technique, electronic sensors, wireless technology, signal sampling, central control, LED displays and LED lighting products.

Intelligent LED lighting systems was composed of four main sections: central control system, data sampling sensor group, guiding system and LED lamps.

 

Central control system used the most advanced ARM9 2440 series, 400MHz frequency, having more than 130 multi-function I/O ports, 24 external interrupt resources and several popular peripheral interfaces.

 

Occupancy sensors, voice-activated sensors, microwave sensors, ultrasonic sensors and ambient illumination sensors constitute the entire data sampling sensor group. These sensors are normally installed on the top of each carport. Among them, ultrasonic sensors play an important role in sensing cars movement.

 

Guiding system is actually a series of instruction set which has been embedded into CPU in advance. After collecting enough information from data sampling sensor group, guiding system will search the nearest vacancy from built-in database and transmit the corresponding information to drivers though broadcast or other indicative marks. Guiding system is a daring design of intelligent LED lighting systems. It has nothing to do with green concept but, to a large extent, realize the complete replacement of labor with computers.

 

LED lamps are controlled by lamp triggers mounted inside of walls. This part is the terminal of the entire intelligent lighting system and also a user interface.

 

Intelligent LED lighting systems were well received after launch. Experts indicated that more and more intelligent LED lighting products applications should be and will be developed and finally into our daily lives.

 

 

sunshine systems led grow lights in LED Tubes

LED fluorescent tubes are the latest product of the led family, but also fluorescent alternatives, constitute mainly of white LED chip module (sunshine systems led grow lights) . The advantages of long life, no flicker, no radiation, energy saving, environmental protection, the advantages of combination of all the fluorescent one.

On the other hand, LED fluorescent tubes  (sunshine systems led grow lights)  installation are very simple, the installation will remove the original fluorescent starterand put LED fluorescent tubes. LED fluorescent energy-saving up to 50% more than the life expectancy of more than 10 times the ordinary lamp, almost maintenance-free. The scope of application: offices, factories, shopping malls, schools, home and other indoor lighting.

sunshine systems led grow lights in LED Tubes

LED fluorescent tube has the advantage of finishing summarized as follows:

1. Green lighting, environmental stresses
Traditional fluorescent lamps contain mercury vapor, if broken mercury vapor will evaporate into the atmosphere. LED fluorescent do not use mercury, and LED products not containing lead, has protective effects on the environment. LED lighting is recognized as the green lighting of the twenty-first century.

2. Efficient conversion
Traditional lamps will produce large amounts of heat, LED lighting is energy all is converted to light, will not cause waste of energy. And file, the clothing will not fade phenomenon.

3. Quiet and comfortable, no noise
LED lighting does not produce noise, the occasion for the use of sophisticated electronic equipment for a good choice. Suitable for the library, the office and the like occasions.

4. Soft light, no flash
Traditional fluorescent lamp use is alternating current, so per second will produce 100-120 times the strobe. LED lamps, AC power directly converted to DC, and will not produce flicker, eye protection.

5 UV, less mosquito
LED lamps do not produce ultraviolet light, it will not be as traditional lamps, there are a lot of mosquitoes around the light source side. The room will become more clean and tidy.

6. Adjustable voltage and a wide range of
Traditional fluorescent lamp is lit by high-voltage rectifier release, can not be lit when the voltage drops. LED lamps  (sunshine systems led grow lights) can be lit within a certain range (80V-245V) voltage, but also adjust the brightness.

7. Longevity, energy-saving and low cost
LED fluorescent lamp power consumption is 10 times below one-third of the traditional fluorescent lamp life is also a traditional fluorescent lamp, the long-term use without the need to replace, reduce labor costs. More suited to the occasion difficult to replace.

8. Sturdy solid, very safe
LED lamp used in epoxy resin rather than glass, more robust solid, and even hit the floor LED will not easily damaged, you can safely use.

Analysis for low price LED bulbs

Although LED lights are more advanced than traditional lamps in almost every aspect, they can hardly be accepted by ordinary family due their high prices. The retail price of a 5W LED bulb, which is equivalent to 20-30W filament lamps, is between 50 yuan and 100 yuan, much more expensive than energy-saving lamps. Same as energy-saving products, the exorbitant prices made LED lighting products become articles of luxury. After nearly 15 years development, Chinese LED lighting manufacturers have gradually realized the seriousness of the problem and spent their money and energy more on developing more cost-effective LED products. Low price LED bulbs is part of the plan.

 Although LED lights are more advanced than traditional lamps in almost every aspect, they can hardly be accepted by ordinary family due their high prices.

Thank to the fierce competition, LED lighting sources, new generation LED drivers, even aluminum shells were forced to drop prices in past few years. This is a right time to produce low price LED bulbs.

 

Market followed the pyramid law. Products with high prices can only occupied a very limited space on the top end. With the reduction of prices, the market space will expand exponentially. Although low price LED bulbs may in the bottom of the pyramid, they will become a mass product that most people can afford.

 

If we can limit the cost of a LED bulb within 8-25 yuan and consequently the market price 15-35 yuan, these LED bulbs will remain in the same price level as energy-saving lamps. As the fourth generation lighting sources, LED really rapidly occupied the entire lighting market and let the filament lamps and fluorescent lamps be history.

 

The design of low price LED bulbs should follow the principle of cost reduction. Generally, LED bulbs are comprised of LED lighting source modules, constant current drivers, lamp heads, covers, cooling sections, etc. Similar construction for LED tubes. The key point is how to keep the cost down for each section. LED lighting sources should have higher lighting efficiency, lower heat generation, better cooling and more cost-effective. Constant current drivers using PSR isolated circuit, less electronic components, higher power factor. These are common sense in LED lighting industry. But it is impossible to give consideration to every aspect and lower the cost at the same time. There must some trade off.

 

 

super bright led headlamp in SMD

1. The role of a plastic patch LED Lights
SMA, surface mount adhesives, for wave soldering and reflow soldering, and is mainly used to components on the printed circuit board, the general dispensing or stencil printing method to allocate in order to maintain the components in printed circuit position on the board (PCB), to ensure that components are not lost in the transmission process on the assembly line. Paste components into the oven or welder heating reflow sclerosis. With the so-called solder paste is not the same, after a heated hardening, and then heating it will not melt, thermosetting plastic patch process is not reversible. The use of SMT chip (super bright led headlamp) adhesive effect due to the thermal curing conditions, the connecting object, the equipment used, the operating environment differ. When used according to the production process to choose a plastic patch.

super bright led headlamp in SMD

2, the composition of the plastic patch LED STREET LIGHT
PCB assembly used in the majority of surface mount adhesive (SMA) are epoxy resin (epoxies), although there are polypropylene (acrylics) for special applications. After high-speed dispensing system into the electronics industry to learn how to deal with a relatively short shelf life products, epoxy resins has become more mainstream glue technology worldwide. Epoxy resins generally provide a good adhesion on a wide range of circuit board, and has very good electrical properties. The main ingredients: the base material (ie, the main high molecular material), fillers, curing agents, other additives such as.

super bright led headlamp in SMD

3, the intended use of the adhesive patch LED TUBES
a wave soldering to prevent the components off (wave soldering)
b. reflow to prevent the other side of the components off (double-sided reflow soldering process)
c. to prevent the components of displacement and stand at (reflow soldering process, pre-coating process)
d mark (wave soldering, reflow soldering, pre-coating), printed boards and components, bulk changes, marked with plastic patch.

4, adhesive patch used classification
a dispensing type: on the printed circuit board through dispensing equipment in Sizing.
b Squeegee type: the printing of steel mesh  (super bright led headlamp) or copper mesh coated scratch sizing.

The final temperature will affect the shape of viscosity and gel point, most modern dispensing machines rely on the needle mouth or chamber temperature control device to maintain temperature above room temperature of the plastic. However, if the PCB temperature increased from the preceding process, the outline of the gel-point  (super bright led headlamp) may be damaged.

Bright LED lighting in Asia entered a golden period of development

Several Asian countries as early as in 3 to 4 years ago to LED Lights industry development and product promotion strategy, such as Japan’s twenty-first Century lighting plan”, Korean “solid state lighting plan”, Taiwan “New Century Lighting Development Plan” in China, the “semiconductor”, the” semiconductor lighting products application demonstration project” plan, these countries level of semiconductor lighting planning reflects the LED lighting industry development, industry economy and environment energy efficiency value. The countries are actively promoting the LED lighting plan, LED bulbs will be listed as priority lead-in lighting products; LED road lamp switch is also like a raging fire, and they estimated that in 2013 global bright led lighting product permeability will further enhance the nearly 2 percent.

Bright LED lighting in Asia entered a golden period of development

In 2010 China’s LED industry total production value achieves 120 million, amount to more than 4000 enterprises, over the past 5 years the average growth rate of 35%, more than 4000 enterprises, over the past 5 years the average growth rate of 35%, more than 35%, more than 2010 40%. Within in the next 5 years the market size will reach 500 million yuan. Application of LED products space wide, from lighting to ordinary furniture, lighting, and then to the city landscape lighting engineering, lighting, decorative lighting and other fields, the market potential is tremendous. Nearly 10 years of LED cost every year in the fall of 2015, the price of product LED has the potential to reduce to 1/5 in 2010, when the general lighting market penetration rate will rise to 50% in 2012, with more than 75% LED lighting market share.

LED lighting industry in Asia entered a golden period of  development, a positive attitude in all enterprises for the bright led lighting is constantly inject new elements and more intense competition. The traditional lighting companies actively develop the LED lighting product line, to actively develop the LED lighting product line, to the semiconductor manufacturing enterprises as the main business focus on the LED lighting to enhance the quality, the great potential of the emerging industry to stimulate a large number of rising star, its fast catching up with the pace of the first enterprises can not lax. Under the constraints of a variety of factors, Asia bright led lighting industry inevitably go through a period of chaotic competition period.

Resolutions for LED tube drivers

Presently, more and more LED lighting products are used in our daily lives, from outdoor lighting applications to indoor lighting applications. LED is new developed technique which is more environmental friendly, more durable, more easily to control and of course can save more energy. LED tube is one of the most widely used indoor LED lighting products.

Presently, more and more LED lighting products are used in our daily lives, from outdoor lighting applications to indoor lighting applications.

LED tubes drivers can be divided into two types: isolated drivers and non-isolated drivers.

 

The input and the output of an isolated driver are “blocked” by transformers. These transformers can improve the security of the entire device but reduce the efficiency (around 85%) as well. Another disadvantage is that these transformers are too large to be put into the limited space within LED tubes.

 

Different from isolated drivers, the input and the output of non-isolated drivers are connected directly by circuits. Although these drivers are more efficient, they are somehow life-threatened. Currently, the most commonly used LED tube drivers are non-isolated BUCK drivers: convert AC to DC through rectifiers and meanwhile drop voltages through Buck block to maintain a constant current.

 

These improved drivers are much simpler in circuit design, smaller than isolated drivers. The normal efficiency of them is 80% ~ 90%. One can support more than 100 LEDs (in cascade or in parallel or both). However, these LED tube drivers have their own defects. Since non-isolated drivers will introduce the high energy from input to output, risking user’s live. To solve this problem, an insulated PCB will be inserted between AC input and aluminum cover. This design can block as high as 2000V voltage, even so it cannot pass the CE Certificate.

 

Comprehensively, both of isolated drivers and non-isolated drivers have their own advantages and disadvantages. Non-isolated drivers think more of efficiency, reducing energy consumption; while isolated drivers are safer to use. In fact, most people intend to use isolated drivers due to their small sizes, high efficiencies, low costs, more cost-effective.

 

LED tube drives can be divided into internal drivers and external drivers. LED tubes using internal drivers can directly replace the traditional fluorescent tubes without any changes. There are two different internal drivers: 1. Rectangular driver, installing within the aluminum shell. It is less practical due to the unevenly heat distribution. LED chips around the power supplier will continuously worked in high temperature. LED tubes using this kind of drivers usually have shorter service life. 2. Divide the entire power supplier into two parts and mounted separately on both sides of the tube. Because of the limited space of tube ends, design is more complicated.