Tailored power management and LED technology for automotive lighting
Solid-State Lighting; SSL is a driving technology in the automotive field. It not only provides some new features, higher safety, design flexibility, easier integration with control systems and electronic components, but also has greater lighting design. The degree of freedom allows every car manufacturer to show its own style and philosophy.
The vehicle electronic control system has many functions: some are related to the windshield wiper system, and others are related to the air-conditioning system. The power management system must not only drive lighting, but also support infotainment equipment to provide a comfortable and safe driving experience.
Through the development of new functions and electronic control systems, LED technology is constantly being updated. Modern design involves not only the light source, but also the shape, projection and image of the light source itself.
The main reason for the success of LED technology is the lower color temperature (usually 5,000K), which the appearance of the car has a stronger sense of technology and metal texture. Its application is embodied in many aspects, which can produce a thin and uniform light guide, thereby further adding aesthetic and personalized characteristics to the car. In addition, because the LED has higher light intensity and safety, it can also provide a good projection depth.
Power management
The key factors for the widespread application of LEDs in the automotive field are its insensitivity to vibration, long service life, high energy efficiency, and complete controllability of the light source. The easy controllability of LEDs naturally also makes them an ideal choice for smart lighting systems to adapt to the vehicle and the surrounding environment. However, in order to drive the LED correctly and achieve high-efficiency light output, current control independent of the power supply voltage is required.
Therefore, a better solution for driving LEDs is to use a current control circuit. LEDs usually require constant current to produce consistent light output: LED drivers must be able to vary the output voltage to maintain a constant current. The output voltage depends on many parameters, such as the LED manufacturing process, mold temperature, and the number of LEDs connected in series.
All switching regulators and LED display drivers used in the automotive industry meet AEC-Q100 requirements. MAX20090 is a single-channel high-brightness LED driver suitable for automotive headlight applications, such as high beam, low beam, daytime running lights, direction indicators, fog lights and other LED lights. LMR23610ADDA is a Simple Switcher synchronous step-down converter in an 8-pin PowerPAD package. This 36V, 1A synchronous buck regulator is suitable for various applications, has a wide input voltage range from 4.5V to 36V, and uses peak current to control the circuit. NCP3065 is a monolithic switching regulator designed to provide constant current to power high-brightness LEDs. The component has an input voltage up to 40V and can work at 12VAC or 12VDC.
LED solutions
Car headlights are high-tech lighting devices that play a very important role in design and safety. LED technology provides a brand-new solution whose service life is equal to the service life of the vehicle, and its energy consumption is only one-fifth of other solutions, thereby reducing fuel consumption and carbon dioxide emissions.
In recent years, the concept of indoor environmental lighting has become popular. For example, a single color such as orange can harmonize the internal and external brightness of the vehicle, thereby reducing the fatigue of driving at night.
RGB static lighting started in 2010, it can bring a pleasant atmosphere to passengers. After that, the market's demand for dynamic lighting effects in different scenarios has gradually increased, such as welcome lights when people enter the car, and driver warning lights in emergency situations (pre-collision and blind spot warning).
RGB ambient lighting is complicated and expensive, and it requires a lot of investment in calibration, manufacturing, and testing equipment. Designers are always faced with the problem of mixing and rendering various different RGB LEDs. This phenomenon is mainly caused by two factors: intensity and wavelength changes in the color and brightness range, and dependence on forward current and temperature.
Based on this, DOMINANT has launched a new series of products called seddLED (Smart Embedded Digital Driver LED), which is a digital LED that integrates RGB LED, LED driver and advanced communication link in a single package.
seddLED (Smart Embedded Digital Driver LED).
"From the design of the concept car, we will see that car seat cushion lighting, roof lighting, full-environment lighting and augmented reality (AR) head-up displays (HUD) will become the future development trend of automobiles." DOMINANT Marketing Director YY Lim said: "Body lighting, car-to-car or car-to-pedestrian communication displays, and sign projection lighting will soon appear. When autonomous vehicles become more and more popular, these new trends will soon be realized."
SeddLED3.0 can control RGB color and brightness through software, and has been pre-calibrated to D65 white point. The accuracy of 1,400 mcd is about three SDCM steps. In addition, it also provides a 2Mbit/s half-duplex differential control bus, and a refresh rate of 52.5ms (5.25ms per 100 LEDs). Its built-in temperature sensor can perform temperature compensation immediately and automatically, and has a self-diagnostic function.
The package also uses a gold lead frame, which has excellent corrosion resistance, and has passed the automotive AEC-Q100 and AEC-Q102 standard certification. seddLED3.0 has greater design freedom and can create different atmospheres in the passenger cabin.
On the market, Nichia and Infineon have provided a design solution for high-resolution (HD) lighting equipment for front lighting applications with more than 16,000 micro LEDs. Compared with the existing HD solution, this new component can provide high-resolution light for the driver's entire field of view.
Daytime running lights are the most common application of LED technology in the automotive field. Due to the small size of the light source and the versatility of high brightness, LED systems can easily integrate new optical designs into automotive headlights.
OSRAM also continues to focus on the automotive field, providing LEDriving lights for automotive interior and exterior lighting, bringing complete projection and signal solutions. For projection lamps, HL series (low beam and high beam) and FL series (fog lamps) can be used to match the full range of signal lamps (SL). LEDriving HL for low beam and high beam can replace H4, H7, H11 and HB4 halogen lamps.
The use of close-up multi-chip LED light source and total reflection technology can achieve precise light-dark distinction (clear separation between light and shadow) and significantly reduce diffuse light, which is conducive to improving the depth of illumination and reducing glare.
The most advanced solution in headlight LED technology is based on the Matrix LED system, a dynamic LED array that can provide automatically adjusted depth light to prevent glare from oncoming vehicles.