High bandwidth current sensor delivers excellent performance for SiC MOSFET applications

LEM has introduced a unique new high bandwidth (1MHz) open-loop sensor able to current sense in some of the severest environments. This new addition completes the entire range of sensors providing the industry's best performance over four nominal currents. The low power consuming HOB-P series of current transducers was produced precisely to satisfy high bandwidth sensing demands when employing fast-switching SiC MOSFETs in high-voltage pulsed-power circuits where fast and flexible high-voltage pulses are crucial.

With a market-leading response time of <200ns – compared to average response times of around three microseconds – the sensor can measure DC, AC or pulsed current up to 250A. Due to a pick-up coil on the company's ASIC, the sensor can react like a current transformer. At the same time, it is ideal for WBG power electronics use cases and applications that need enhanced immunity to the dv/dt (acceleration) issues that SiC power modules are prone to. The new sensor claims to provide far better dv/dt behaviour and lower noise than other sensors on the market.

Some of the highly demanding applications ideal for the new unit – with an operating temperature range of -40C to +105C – include hand-held plasma cutters, welders and DC-DC converters.

Other applications are UPS, switched-mode power supplies, AC variable speed and servo motor drives, and static converters for DC motor drives.

Bastien Musy, VP of Global Product Management for LEM, says: "This sensor provides unmatched performance, combining a high bandwidth and a very short response time. It all started with a customer using high-frequency SiC MOSFETs who needed a top performance solution that delivered faster response times and larger bandwidth in a smaller footprint. We are delighted that we were able to create an open-loop solution that not only perfectly meets the requirements from the customer but also addresses broader market expectations."

The HOB-P series of transducers is CE marked and covered by LEM's five-year warranty.