New-Tech Europe Magazine | March 2018

Automotive Special Edition

the power efficiency. In most of the case some MHZ precisely 1-2MHz. The Buck converter is the supply circuit for the LED is used to transform the boost converter voltage to lower voltage. Usually the output voltage of the boost converter could be around 5V or lower. How Panasonic as components supplier is supporting design engineer to solve their problem andwhichcomponentPanasonic is offering for this application? As a leading supplier for Metal composite, Panasonic is offering Power choke coil. High current one of the advantages of Panasonic metal composite is high current capability, high saturation current. Due to its compact structure or monolithic structure, PANASONIC metal composite coil can achieve high current capability without drastically drop of the inductance value. (picture 3). By applying high ripple current, the inductance will drop almost linearly. In addition there is almost no deviation of the inductance value at different temperatures. As a result this characteristic of the Power inductor is contributing to the stabilization of the Boost and buck converter circuit. Drastically drop of the inductance value will lead to a dysfunction the circuit since no inductance value or less inductance value will lead to an instability of the output voltage of the boost converter and the buck converter.

Picture 1: Automotive Lighting

for both seeing and being seen. Lighting is one of the most growing application in the automobile. The growing demand of lighting in vehicle is mostly due to safety and driving comfort purpose. From the interior to the car exterior (headlamp, rear lamp), the vehicle is surrounded by Light. Due to this growing demand, Tier1 customer are developing innovative lighting systems such as Adaptive front lighting system (AFS), Adaptive cut- off line, vertical cut-off line, LED Matrix Beam. In the latest system for example a total of 25LEDs per headlight can be operated on full power. in order to design such system, electronic designer are facing the problem of developing ECUs with low power consumption in order to drive one or more LEDS, to find components working at high frequency (some MHz). In order to understand what is the benefits and which passive components Panasonic are offering for this application, let us answer to

the below questions. How a design circuit is looking like for such an Lighting system? The block diagram of such an design is based on Filter circuit, Boost converter circuit and buck converter circuit. The Filter circuit is designed to absorb noise coming outside world or other near design ECU or component, allowing the ECU the work properly in its reserve frequency range. the boost converter circuit is designed in other to boost input voltage means to transform the Input voltage to higher output voltage. In most of the case from 12V to 70V. Usually such a boost converter is also working at a certain frequency in other to improve

Picture 2: Circuit Block diagram of Lighting system

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