Texas Instruments (TI) has launched a 650V Gallium Nitride (GaN) FET with a silicon driver in the same package for industrial designs.
The GaN transistor operates as an ideal diode rather than depletion or enhancement mode to simplify the design and management of flexible, high power systems up to 5kW in a QFN package. “This is a milestone not just for TI but for GaN in general that the technology has reached this level,” said Steve Lambouses, Vice President & GM of High Voltage Power at TI.
The combination has been under test with customers since 2018 to gather 40m hours of reliability data before the launch. “The discussions now are not about reliability, they are about how to optimise the system, optimise the topologies, how to use the ideal diode mode, the digital reporting, that’s what’s exciting and very different from the earlier days of GaN,” said Lambouses.
“For every 1W you save in efficiency you can save 1W in cooling so you get a magnifying effect in reducing losses,” he said. “When you think about switching 5kW in a QFN package that’s unique, the thermals and the technology that has to come together in a low profile package. It’s combining the package with the low inductances for the switching speed. 5kW has been possible for a long time but in large packages. This combination comes from putting the silicon driver in with the GaN to provide the power with a small volume.”
The driver in the LMG340x supports a switching frequency of 2.2MHz for 99 percent conversion efficiency. This higher frequency also reduces the size of the magnetics by 56%, reducing the size and weight of onboard chargers and inverters. The on-resistance of 30 mΩ of the epitaxial lateral GAN FET reduces the thermal losses and the size of the heatsink required.
“You don’t see integrated driver and controller at these power levels,” he said. “It’s uniquely different in terms