STi2Fuse Automotive Switches for Power-Distribution Applications

STi2F automotive controller N4454I

The STMicroelectronics VNF1048F automotive high-side switch controller combines enhanced system-protection and diagnostic features with ST’s I2-t silicon-fuse technology.

As the first in ST’s new STi2Fuse family with integrated I2-t protection, the VNF1048F is compatible with 12V, 24V, and 48V automotive power subsystems (board nets). Its flexibility is ideal for the latest automotive zonal electronic/electrical (E/E) architectures that boost efficiency and reliability while supporting increased electrification and extra functions for smart driving.

The feature-rich and adaptable VNF1048F has a serial peripheral interface (SPI) for a host microcontroller to configure and monitor system-protection and diagnostic features. These include under-voltage and over-temperature protection, thermal protection for the external high-side MOSFET, desaturation shutdown, and I2-t fuse settings. High-precision digital current sensing is built in. Analog-to-digital converters (ADCs) for monitoring the temperature-sensing thermistor voltage, output voltage, and MOSFET drain-source voltage are also integrated.

ST’s I2-t fuse, a defining feature of the STi2Fuse product family, provides superior fast-acting, resettable, and reliable over-current protection. Silicon fuses also help simplify vehicle wiring harnesses and reduce weight by eliminating user-accessible fuse boxes and the associated cabling and installation overheads. The savings in weight contribute to improving vehicle performance, including extended driving range and reduced CO2 emissions.