LEDs In Automotive Exterior Lighting

  • 337
  • Jimmy at
  • November 09, 2017

LEDs In Automotive Exterior Lighting


LEDs In Automotive Exterior Lighting  Red LEDs In Automotive Exterior Lighting


LEDs are taking the automotive industry by storm due to significant advantages over traditional technologies. The superior clarity of the white light in led headlights improves driver reaction time. Adaptive front-lighting systems, enabled by led matrixes, produce fast, complex light-pattern changes that improve visibility for drivers in poor light conditions. At night, in response to the beams of an incoming car, AFS can automatically adjust the light pattern, preventing the oncoming driver from being blinded by harsh lighting.
LEDs have become important components in car headlights bulbs. In addition, the led illumination rise-time is twice as fast as that for incandescent sources, so that Led-based brake lights illuminate quicker and provide advanced warning to drivers, increasing road safety. Finally, leds consume less power than their incandescent counterparts, leading to substantial advantages in fuel consumption. Led controllers, the electronics that operate leds, play an important part in preserving and enhancing the inherent led qualities of clarity, speed, and efficiency.
LEDs power. Leds have many automotive applications, and are used in diverse configurations from a single led to led strings and matrixes. High-brightness leds require constant current for optimal performance. The current correlates with junction temperature and hence color. Accordingly, HB leds must be driven with current, not voltage.
Dimming is a ubiquitous function in many automotive applications and an important safety feature for led headlights bulbs. The human eye can barely detect light dimming from 100% to 50%. Dimming must go down to 1% or less to be clearly discernable. With this in mind, It’s not surprising that dimming is specified by a ratio of 1000: 1 or higher. Given that the human eye, under proper conditions, can sense a single photon, there’s practically no limit to this function.
LED Controller Characteristics, to be most effective, the led controller must accommodate a wide input-voltage range and have a fast-transient response as discussed earlier. A high, well controlled switching frequency, outside the AM frequency band, is required to reduce radio-frequency interference and meet EMI standards. Finally, high efficiency reduces heat generation, improving the car led light system’s reliability.
The Headlight System, Sophisticated led headlight bulbs systems utilize a boost converter as a front-end to manage both the variability’s of the input voltage and the EMI emissions. The boost converter delivers a well-regulated and sufficiently high output voltage. Dedicated buck converters, working from this stable input supply, can then handle the complexities of controlling the lamp’s intensity and position by allowing each buck converter to control a single function, such as high beam, low beam, fog, daytime running lights, position, etc.