Advanced automotive lighting solution for case analysis

With the development of automobile industry, more and more advanced lighting technology is to get more application in the car. Among them, the light emitting diode ( 领导) Lighting has the incomparable virtues than the halogen lamp and xenon lamp, such as long service life, fast response time, energy conservation, environmental protection, etc. , to speed up the pace of a large number of used in automotive lighting.

various semiconductor as applied to primary energy efficient electronic products of high performance silicon solution provider, which is based on advanced semiconductor technology, continuous commitment to car headlamps lighting, instrument panel backlighting, interior lighting, door and rear lights automotive lighting applications, including standard and custom products rich, such as stepper motor drives, LED drive, drive xenon lamp, halogen lamp driver, LED backlight driver, etc. ; Especially in the headlamp adjustment and deflection with xenon lamp drivers application-specific integrated circuit ( ASIC) And become a DE facto standard stepper drive leads the market.

development trend of automobile headlamps

the road line most cars equipped with headlamps still for halogen lamp, mainly provide low beam and high beam lights ( HB) Function. Dipped headlights of a typical power consumption for 55 W, light output is about 1000 lumens. In comparison, the launch has more than 10 years of high intensity discharge lamp ( 藏) Technology of power consumption of 35 W, light output is about 3500 lumens. Because the HID lamp luminous intensity is high, there are risks to make to close to the car driver blinding, for security reasons, some countries require dipped headlight with horizontal position automatic adjustment function, with high pressure cleaning device. As time goes on, more and more HID lamp will be the high beam functions into double xenon lamp scheme.

due to the increasingly stringent requirements, energy saving halogen technology is still used for headlamps lighting, automobile design increasingly turned to the LED lighting. LED lighting can provide enhanced model selection, implementation 'instant' lighting, allow the brightness control of power from 0% to 100%.

another important trend of automobile headlamp application, it is adaptive headlamps system ( AFS) Provides the beam deflection function to optimize the lighting of the bend, and the adaptive headlamps ( ADB) Based on the actual environment in real time adjustment of beam. Stepper motor is for AFS and ADB control function.

semiconductor manufacturing for automobile headlamps lighting applications provide broad cast products, from the general drive plan to step into the bulb, LED driver and xenon lamp driver, etc. , to name but a few.

various semiconductor auto lighting solution example

1) Headlamp adjustment and deflection

ansion beauty the AMIS - of the semiconductor 30623 single chip micro step motor drive is suitable for the headlamps level adjustment and deflection control. It integrates the controller and interface of LIN, LIN host is used to implement remote connection of special mechanical and electrical integration solution design. The device through the bus receiving position adjustment instruction, then drive motor coil to the desired location, using current, speed, acceleration and deceleration configuration parameters. AMIS- 30623 also can also detect motor stalling.

ansion beauty and two other semiconductor devices can also be used for the above application, NCV70521 and NCV70522 are based on single chip micro stepper motor drives, with current conversion tables and SPI interface. NCV70522 include embedded 5 V voltage regulator and watchdog reset function. This device can be used as a peripheral drive, from micro-controller micro 'next step' command, and make the motor coil current and speed synchronization required. Integration of SPI bus allows the parameter Settings and feedback.

　　2) Advanced LED headlamps power ballast and dual LED drive

various semiconductor NCV78663 single chip, intelligent LED headlamp drive can realize high beam, low beam lights, auxiliary lamp of daytime running lights, clearance, corner lights, turn signals, and the single chip control of fog lamps. NCV78663 integrates digital dimming, SPI programmable Settings and built-in diagnosis, provides a set of integrated, highly efficient electric forming headlamps control solutions.

　　3) Combination of LED taillight linear current steady flow and the controller

various semiconductor NCV7680 including eight linear programmable constant current source. Adopt NCV7680 system design can realize the two level of brightness, one is the brake lights, one is the rear lighting; Can also achieve the optional PWM control, this is the preferred method of that move light LED. Fixed frequency PWM generator can provide flicker-free lighting. The optional external ballast FET contributes to the realization of the power distribution requires high current design.

in order to support the LED string combination of common car taillight ( RCL) Configuration, NCV7680 provides no matching output to drive the string of leds, and adopts one resistor to set current. Separate LED string driver can ensure equal distribution of electric current between the LED string.

NCV7680 can serve as an independent device, also can be used as additional support for the complex system circuit. According to the operation, pressure controller additional LED can be connected to an LED string. Its typical applications include composite tail lights, daytime running lights ( DRL) Brake lights, fog lamps, central high ( CHMSL) Array, turn signals and other external modulation applications, liquid crystal display ( LCD) Backlight, etc.