High power LED lamp beads using the proposed
The author：admin Update time：2009-8-25
Dear High Customer: Thank you for using Xin Hao power LED light source beads, in order to play better the performance of our products, protection of customers use less during the fault, especially the following installation recommendations for reference only, large power LED products and components in the application of heat during welding electrostatic protection has a significant impact on their properties, applications need to rise to end customers very seriously.
1, cooling: As the semiconductor light-emitting diode chip technology of the restrictions, LED photoelectric conversion efficiency remains to be improved, especially LED, higher power, some more than 60% of the heat energy Jiang Bian Cheng Shi Fang (With development of semiconductor technology, photoelectric conversion efficiency will be gradually increased), which requires end-user in the application of high-power LED products, when to do a good job cooling to ensure that high-power LED products work.
Our company based on product characteristics and long-term experience of aging test data concerning heat suggestions for reference purposes only!
1. Heat sink requirements.
Appearance and materials: If product seal ask for much, can occur outside the direct flow of air environment, the proposed use with aluminum or copper fin heat sink.
2. Effective cooling surface area:
1W high power white light LED for the (other colors the same) I recommend the Secretary effective cooling fin surface area ≥ 50-60 total square centimeters. 3W Products Recommended heat sink for effective cooling surface area of the sum ≥ 150 square centimeters, more power to increase, as the case and test results, as far as possible ensure the heat sink temperature does not exceed 60 ℃.
3. Connection method:
High Power LED substrate and heat sink to connect the two, please contact surface to ensure smooth, good contact, the two contact surfaces to enhance the degree of integration, the proposed bottom of the LED substrate surface coated with a layer of heat sinks or thermal grease (thermal conductivity of thermal grease ≥ 3.0W/mk), thermal grease required coating uniformity, adequate pressure then screw stationary.
Second, electrostatic protection: LED is a semiconductor device, more sensitive to static electricity, especially for white, green, blue, purple LED to the prevention of static electricity and eliminate static electricity work
1. Generate static electricity: ① friction: In daily life, any two objects of different materials after contact with the separation can be static, and static electricity of the most common way is friction power. The better the insulation material, the more likely friction power. In addition, any two objects in contact with different materials after separation, can also generate static electricity. ② induction: for conductive materials, the electronic energy in the free flow of its surface, such as placing an electric field, due to homosexual exclusion, opposites attract, positive and negative ions will be transferred, the surface will result in charges. ③ Transmission: for conductive materials, the electronic energy in the free flow of its surface, such as with the charged object access] contact, charge transfer will occur.
2, electrostatic hazards on the LED:
① instantaneous electric field or current by the heat produced, so that LED local injury, showing rapid increase in leakage current can still work, but the decrease in brightness (white light will change color), life impaired. ② LED due to electric field or current damage the insulation layer, the device does not work (completely destroyed), showing dead lights.
3. Electrostatic Protection and Elimination:
The entire process (production, testing, packaging, etc.) All staff in direct contact with the LED to be good measures to prevent and eliminate static electricity, mainly: 1, anti-static floor workshop and laying good ground. 2, anti-static table to table, the production machine grounding a good [. 3, the operator to wear anti-static clothing, with anti-static wrist strap, gloves, or foot. 4, ion fans, electric soldering iron good grounding measures. 5, anti-static packaging materials used.
Third, welding: welding Note select constant temperature soldering iron, soldering temperature is 260 ℃, a soldering iron in contact with the LED pad for no more than 3S (note electric soldering iron must be grounded, the operator should wear a static bracelet or blown-ion fan)
4, drive circuit: LED followed by high-power diode volt-ampere characteristic curve, if the floating voltage corresponding drive current drift very easily damaged lamp beads, it recommends that customers use the more stable constant current drive power, or IC, which Do not use power or constant voltage driver IC.
