In the past two years, LED heat has been hot, but the current technical problems of LED also affect the promotion and application process. To this end, EDN China has held the second LED Technology Forum at the request of readers, and technical experts from NXP, Tyco Electronics, NS, LeCroy, Longmao Microelectronics, IR, Shanghai Sijing Microelectronics and Avnet , for LED adjustable light source, circuit and overheat protection, fast test, LED fluorescent lamp application prospects, LED drive circuit design, LED display and drive IC technology and market and LED lighting design service topics, for the scene more than 200 listeners made content A detailed report. For more details, please visit the EDN website at http://events.ednchina.com/led to view the speech PPT.
MOSO Class
II Programmable LED Driver supports 0-10V, PWM, timer step dimming or DALI control
from 75W to 320W. It can reprogram the output by a software or infrared controller. Class II outdoor Driver is IP67
waterproof, with build-in surge protection. It provides a Dim-to-off mode with
low standby power. MOSO Class II
Programmable power uses extruded-metal housing and fully glue-potted for
good dissipation.
MOSO developed Class II Programmable LED Driver series with special isolation
design for global market especially for the Europe. All Class II LED Drivers are certified with CCC, CE, TUV, ENEC and CB
standards.
MOSO has set several distributors in
Europe, United States, Latin America, Asia and Australia. All MOSO Class II Programmable power suppliers provide
5 years global warranty. In case of any failure, customers can get replacement
either from MOSO directly or any one of MOSO distributors.
MOSO always dedicates to providing
professional outdoor lighting solutions. Please feel free to contact our sales
team if you need any support!
Class II Programmable LED Driver Class II Programmable LED Driver,Class II Programmable Dimmable Driver,Dim-to-off Class II Programmable Driver,Class II Programmable Outdoor LED Driver Moso Electronics , http://www.mosoleddriver.com
NXP Semiconductors senior application engineer Dai Taichu said in his speech entitled "More compact, durable and efficient lighting solutions", NXP's high efficiency, current control input dimming solution for high efficiency isolated and non-isolated power dimmable LED drivers The solution supports existing dimmers based on Triac and Transistor to meet different power level requirements, and achieves safe and reliable thermal performance through package design to improve heat dissipation.
Guo Tao, application engineer of Tyco Electronics Shanghai Ruiqi Circuit Protection Department, introduced the "LED lighting synergy circuit protection scheme", saying that both theory and practice have proved that the performance and lifetime of LED are closely related to the operating temperature of the pn junction of LED. When the junction temperature of the LED chip rises by 10 ° C, the luminous flux is attenuated by 1%, and the LED reduces the lifetime by 50%. Overcurrent, overvoltage, and overheating significantly reduce the LED's luminescence performance and lifetime. Therefore, in addition to good thermal design, safe and reliable overheat protection must also be considered.
Li Wei, an application engineer in East China, NS China, introduced the LM3424, a low-end LED controller with overheat protection for outdoor and automotive lighting. Li Wei believes that the three challenges faced by LED lighting systems are thermal management, optical design and drive circuits. The key to the problem is whether the thermal management of LEDs can play a role. Effective thermal management can extend LED lifetime and reduce LED luminous flux output. The extent of the decline. Since many different LED lighting systems are installed inside and outside the car, different LED driver topologies must be used depending on the situation. The automotive lighting system LED driver must be able to operate over a wide input voltage range. Overheat protection: Even in an abnormal working environment, the LED will not be overheated and damaged, and it can maintain a certain brightness. Because the exterior lighting system involves driving safety, its stability is extremely important.
With the LM3424 boost controller's solar LED street light, Li Wei recommends that the solar street light adopt a boosted power supply architecture, which can reduce the number of LED drivers in the lighting system and reduce the cost of the solution. The overvoltage protection protects the LM3424 and external power components from damage due to excessive voltage when the LEDs are turned on. Multiple LM3424 drivers operate at the same frequency, reducing electromagnetic interference and simplifying the system's EMI design. In addition to the original functions, NS's latest product LM3429 includes: high input voltage, high-side current detection, adjustable current detection, nDIM, overvoltage protection, etc.
Li Ke application engineer Hu Weidong pointed out that the LED driver is gradually changing from linear adjustment type (LDO) to switching type, and the efficiency is greatly improved; and with the progress of semiconductor technology, the LED driver is gradually changing from linear adjustment type (LDO) to switching type. Some peripheral power switches and diodes are also integrated into the driver chip, which greatly simplifies the peripheral circuits, but tests their forward current and forward voltage drop at the operating point, as well as reverse leakage current and reverse breakdown voltage. Parameters are becoming increasingly important, and LeCroy oscilloscopes are specifically tailored for power testing.
Mao Yuhai, general manager of Shanghai Longmao Microelectronics Co., Ltd. believes that the only shortcoming of LED fluorescent lamps is the high price. The LED fluorescent lamp has low power consumption, high power efficiency/power factor, long life of 50,000 hours, no mercury, wide color temperature range, no ultraviolet radiation, no electromagnetic radiation, and external power supply can make the voltage at both ends of the lamp lower than 36V safe voltage, not easy to break and so on, it can be said that the use of LED fluorescent lamps today is economically cost-effective. If all LEDs are converted into LED fluorescent lamps in 2020, they can reduce 327 million tons of carbon dioxide, accounting for 11.7% of China's commitments. This is a very significant emission reduction.
IR Advanced Field Application Engineer Wei Weidong "LED Driver Topology" believes that fixed voltage LED driver resistors or linear regulators introduce additional power loss, often included in the LED display, increasing cost and power consumption. Perhaps sufficient for low current applications, but now there are some high current LED arrays that can meet the needs of general lighting. Wei Weidong believes that current-controlled power supplies will become the mainstream of the future.
"The market and technical analysis of LED display and LED driver chips" by Lu Chengchang, vice president of Shanghai Sijing Microelectronics Market and Sales. From 2007 to 2010, the average annual growth rate of China's LED display market will reach 15.1%. The demand will reach 7.55 billion yuan. The advantages and disadvantages of the LED driver chip play an important role in the display quality of the LED display. Sijing Microelectronics SMT5026 is a 16-channel constant current LED driver IC designed for LED display. Built-in CMOS shift register and latch function can convert serial input data into parallel output data format. The product has been Many domestic users recognize and use in bulk.
Hu Xuchuan, an electronic component business development engineer of Avnet, introduced the Avnet LED lighting design service business to the audience. Hu Xuchuan said that one of the most important directions in current LED applications is high-power LED street lights. In the streetlight solution, Avnet can provide customers with: light source, constant current power supply reference design and optical simulation.
