STMicroelectronics has started producing automotive high-side power switches with proprietary intelligent fuse protection and a Serial Peripheral Interface (SPI) for diagnostic data, enhancing resilience and functional safety.
The quad-channel VNF9Q20F is the first in a new line of monolithically integrated devices that combine ST’s advanced VIPower M0-9 MOSFET and STi2Fuse technology. Utilizing patented I2t (current squared through time-to-fuse) functionality, the STi2Fuse turns off the MOSFET within 100µs if excessive current is detected.
As an intelligent circuit breaker, the VNF9Q20F improves boardnet voltage stability and prevents PCB traces, connectors, and wire harnesses from overheating. It also features a capacitive charging mode, allowing harmless inrush currents and normal operation with highly capacitive loads.
Designed for the latest zonal electrical/electronic architectures, the VNF9Q20F is ideal for fuse and relay replacement, ECU isolation, and managing systems active when the vehicle is parked. With 64 programmable current-limit values, the STi2Fuse enables precise overload response.
Internal features include a 10-bit analog-to-digital converter (ADC) and fault registers, providing rich diagnostic information and digital current sense feedback for predictive maintenance. Diagnostics through the SPI and built-in self-test help systems meet ISO 26262 safety integrity levels. An embedded failsafe mode ensures operational status during failures.
The VNF9Q20F is now in production, available in a 6mm x 6mm QFN package, starting at $2.850 for 1000 pieces.
For more information, visit www.st.com/vnf9q20f.
