Ultrafast Medium VF and QRR (200V - 400V)

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ST’s medium VF and QRR 200 to 400 V ultrafast diodes, typically used in applications where switching frequency ranges from 20 kHz to over 100 kHz, feature a reverse characteristic to minimize ringing effects with other inductive devices, while having a VF able to match the power loss budget of the designer.


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.

Thermal-electrical Simulators for Components

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AC Switches Simulator

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Get junction temperature and blocking voltage graphs
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Rectifier Diodes Simulator

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Estimate power losses
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Supports long mission profiles
Provides power loss and temperature graphs
Helps define heatsink thermal properties

Twister Sim

Help select the right ViPOWER Automotive power device
Supports load-compatibility, wiring harness optimization, fault condition impact and diagnostic analysis
Supports various PCB configurations

TVS Simulator

Specify system ratings and surge waveform
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