Ultrafast Rectifiers

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The ST rectifier diode designs deliver performance for applications with very different VF/Qrr trade-offs depending on targeted functions. The minimal power losses of the ST rectifiers range is totally adapted to mains rectification, bypass, boost, bootstrap, freewheel and HF rectification functions. Inside these generic functions, the topology evolution in e.g. resonance or multilevel is followed constantly by suited designs. Ultrafast rectifiers are belonging to the STPOWER family.

This is backed-up by the ST diodes manufacturing industry aimed at serving our customers of all segments, automotive, industrial, computer, consumer and appliance included in a past, present and future focus.


Our best bipolar ultrafast rectifier diodes maintain heavy R&D progress illustrated here by the ‘RQ’ soft diode series for resonant converters.

New 600V ‘RQ’ diodes improve creepage distance and reduce EMI

Thanks to the high-voltage D²PAK package, our new diode series improves the creepage distance and facilitates compliance with the IEC 60664-1 worldwide standard. ST now offers 600 V ‘RQ’ diodes (Rapid & Quiet) – providing a minimum of 3.48 mm between the anode and cathode instead of only 1.38 mm for a standard D²PAK device. Developed for electric vehicle (EV) charging stations, industrial converters, high-power SMPS, snubber circuits and for free-wheeling, these diodes feature a unique trade-off between a soft reverse recovery to reduce electromagnetic interference (EMI) and a low forward voltage (VF) to gain efficiency in all modes of resonant-based topologies.
These 600 V, 15- to 30-amp diodes are also available in an automotive-grade ‘RQ’ series, suited for on-board battery chargers (OBC) and 2- or 3-wheeler battery chargers.


eDesignSuite is a comprehensive set of easy-to-use design-aid utilities ready to help you streamline the system development process with a wide range of ST products.

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