news digest ♦ compound semiconductor ♦ product news
the industry’s first LED driver with dynamic headroom control and multiple outputs for high-power applications that accurately and efficiently drives up to four strings of LEDs. The LM3464, a member of National’s PowerWise® energy-efficient product family, maximizes system efficiency and reduces system complexity and cost in LED-intensive applications such as industrial, street and automotive lighting.
Unlike traditional high-brightness LED drivers that drive current to each string independently, the LM3464 LED driver includes four channels to drive up to 20 LEDs per channel, reducing system complexity and cost.
The LM3464’s dynamic headroom control feature dynamically adjusts the LED supply voltage through the power supply feedback to the lowest level required to provide optimal system efficiency.
Technical Features of National’s LM3464 LED Driver
The LM3464 is a high-voltage current controller with four individual current regulator channels. It works in conjunction with external N-channel MOSFETs and sense resistors to accurately drive current to each LED string. The LM3464 features a wide input voltage range up to 80V to drive multiple LEDs per string, making the LM3464 ideal for LED-intensive applications.
A thermal foldback feature protects the LEDs from unsafe temperatures that can significantly degrade the light output or lifetime of the LEDs. During an over-temperature condition, the thermal foldback reduces the current through the LEDs until the LED junction temperature of the LEDs returns back to a safe operating temperature. This user-programmable feature allows for a more robust and reliable thermal design, helping to ensure the lifetime and light output of the LEDs over time and through temperature variances due to environmental conditions of the fixture.
106
www.compoundsemiconductor.net June 2010
Genesis Photonics orders Veeco MOCVD Systems
Veeco Instruments Inc has announced that it has received orders for multiple TurboDisc(R) K465i(TM) gallium nitride (GaN) Metal Organic Chemical Vapor Deposition (MOCVD) Systems from Genesis Photonics Inc. (GPI)
GPI will use the systems to increase capacity for the production of high brightness light emitting diodes (HB LEDs) being driven by applications such as backlighting, lighting, displays, and automotive applications.
David Chung, Chairman and CEO of GPI, commented, “We have been very pleased with the production proven performance of Veeco’s MOCVD systems already installed in our manufacturing facility. They are helping us to achieve brightness higher than the industry average. It was natural for us to select the K465i MOCVD Systems for our increasing
The dynamic headroom control feature monitors the forward voltages of the LED strings and dynamically adjusts the LED supply voltage through the power supply feedback to the lowest level required. By directly controlling the output of the offline regulator, the LM3464 can eliminate the second stage switching regulator commonly required for offline LED power supplies.
The LM3464 features both pulse-width modulation (PWM) and analog dimming interfaces to allow the user to select between various dimming types for different applications. Protection features include VIN under-voltage lock-out, LED open/short circuit and over- temperature fault signaling to the system controller.
Offered in a 28-pin thermally enhanced TSSOP package, the LM3464 is available for design on National’s WEBENCH® LED Designer at http://
www.national.com/analog/webench.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127