The TO-leadless (TOLL) package has been selected for the 5.4mΩ 750V SiC FETs, with on-resistance ranging from 5.4mΩ to 60mΩ. The FETs are suitable for applications where space is limited, for example AC/DC power supplies ranging from several 100W to multiple kW, as well as solid-state relays and circuit breakers up to 100A.

The company claims that in the 600/750V class of power FETs, the SiC FETs “offer unmatched performance across the main figures of merit for on-resistance and output capacitance”. In the TOLL package, at 5.4mΩ the devices have four to 10 times lower on resistance than competing best-in-class Si MOSFETs, SiC MOSFETs and GaN transistors, continues Qorvo. At 750V, they are also 100 to 150V higher than the alternative technologies to provide an enhanced design margin for managing voltage transients.

Anup Bhalla, chief engineer for Qorvo’s Power Devices business, decribes the 5.4mΩ Gen4 SiC FETs in the TOLL packaging as an important step in the company’s goal to provide multiple device options. “Customers working on industrial applications in particular need this combination of flexibility and cost-efficient power design,” he says.

The TOLL package is 30% smaller in footprint and is half the height of comparable alternative D2PAK surface-mount offerings, says the company. It achieves 0.1°C/W thermal resistance from junction to case and DC current rating is 120A up to case temperatures of 144°C, while the pulsed current rating is 588A up to 0.5ms. This, combined with the low on-resistance and transient thermal behaviour yields an I2t rating approximately eight times better than a Si MOSFET in the same package, according to the company. This contributes to robust performance and immunity to transient overloads. It also simplifies the design. A Kelvin source connection is also provided in the TOLL package for reliable high-speed switching.

The Gen4 SiC FETs implement the company’s cascode circuit configuration, in which a SiC JFET is co-packaged with a Si MOSFET to produce a device with all of the efficiency advantages of wide bandgap switch technology and the simpler gate drive of Silicon MOSFETs.

The TOLL-packaged Gen4 5.4 mΩ SiC FET is included in Qorvo’s FET-Jet free-to-use online calculator, which allows instant evaluation of efficiency, component losses and junction temperature rise for parts used in a wide variety of AC/DC and isolated/non-isolated DC/DC converter topologies. Single and paralleled devices may be compared under user-specified heat-sinking conditions to determine an optimal solution.