Issue link: https://resources.mouser.com/i/1429079
mouser.com/vishay / 25 Vishay develops products to meet the challenges posed by both the traditional automotive environment and the new electrification opportunities. It is crucial to maintain the high- quality standard of existing technology while incorporating electric vehicles' unique features. Vishay developed an automotive-grade standard based on relevant automotive industry quality initiatives to ensure this high quality. This standard includes a detailed design policy to leverage industry best-practices, failure modes and effects analysis (FMEA), and qualitative lessons. Vishay applies rigorous testing to all its products to validate the conditions defined in its standard. We've now explored how Vishay's products address the unique challenges posed by 48V systems, electric car battery charging management, and dashboard sensors. Let's re-cap. 48V Systems 48V subsystems are a vital enabler to the connected EV, as they reduce resistive losses and more efficiently distribute power to electrically-driven features such as electric power steering and the heating, ventilation, and air conditioning (HVAC) systems. They also support battery energy management and waste energy recovery, extending the vehicle range with a single charge. 3KW 48V/12V BUCK-BOOST CONVERTER DESIGN Because manufacturers tend to favor a phased transition to electrification, they design vehicles with 48V and 12V systems. This architecture requires a bi-directional 48V-12V DC/DC converter to provide efficient power transfer between the systems. Vishay developed a 3kW converter design to address this critical need. The design includes six modular 500W power stages that can be activated or deactivated independently to maximize the system efficiency at each operating point. Also, the parallel circuit power-stage construction provides redundancy in the event one of the stages fails. 25KW INVERTER WITH A 3-PHASE TOPOLOGY The variety of hybrid/EV configurations in the automotive market creates the opportunity for an advantaged 48V inverter. Vishay has developed a 25kW 3-phase inverter to optimize the costs of both the inverter and the machine in an efficient packaging envelope. The inverter's MOSFETs provide very high pulsed- drain currents with low junction-case thermal resistance, and its phase current shunts offer a high power-to-surface area ratio with low inductance. Vishay engineers designed the layout to reduce the current path lengths to reduce transients and losses. eFUSE FOR SAFE BATTERY INTERFACE WITH 10KW LOADS The vehicle's high-load functions, such as power steering and electric turbochargers, carry a risk of excessive arcing when using mechanical relays to connect them to the 48V battery. Vishay designed an eFuse for loads up to 200A and 48V on a compact, double-sided FR4 PCB with passive cooling to mitigate this risk. The eFuse connects two bond wireless MOSFETs bi-directionally to prevent current backflow to the battery. Engineers oriented the MOSFETs in parallel (similar to the 3kW converter) to reduce resistance and power dissipation.