40V automotive MOSFETs boost noise immunity, efficiency

October 25, 2016 // By Graham Prophet
STMicroelectronics has added two 40V automotive-qualified MOSFETs in the its StripFET F7 technology, which combines superior switching performance and energy efficiency with very low emitted noise and high immunity to false turn-on.

Key applications for the devices, which have current ratings up to 120A, include high-current powertrain, body, or chassis and safety systems, and the switching characteristics suit them to use in motor drives such as in Electric Power Steering (EPS).


ST's STripFET families use DeepGATE technology to achieve low RDS(on) per die area and low RDS(on) x gate charge (Qg), giving superior energy efficiency in familiar power packages. High avalanche ruggedness is another feature.


STripFET F7 enhances switching performance and maximizes energy efficiency by lowering the body-diode reverse-recovery charge (Qrr) and reverse-recovery time (trr), while softer recovery minimizes electromagnetic interference (EMI) thereby easing demand for filtering components. Optimized device capacitances increase noise immunity, relieving the need for snubber circuitry, and threshold-voltage tuning ensures high false turn-on immunity without requiring a dedicated gate driver. In bridge circuits such as motor drives, the soft diode recovery helps prevent shoot-through currents thereby enhancing reliability.


The 40V STL140N4F7AG and STL190N4F7AG are qualified to AEC-Q101 in the PowerFLAT 5x6 package with wettable flanks. The compact footprint and 0.8 mm profile enable high system power density, while the flank design aids solder-joint reliability and lifetime as well as allowing 100% automatic optical inspection. The 40V automotive-qualified STripFET F7 MOSFETs are priced at $0.92 for the STL140N4F7AG and $1.25 for the STL190N4F7AG (both 1000).


ST; www.st.com/ag-40vmosfet and www.st.com/stripfetf7