We always stress how efficient electric cars are. It is important to have that in mind, and Jason Fenske recently reminded us of that with a video about the huge impact tires can have on EVs. Texas Instruments reminds us that it can be true even for a tiny component, such as a transistor. To prove that, it developed a new generation of gallium nitride field-effect transistors that can make onboard chargers and DC-to-DC converters 50 percent smaller.
These electronic components are also called GaN FETs. The ones created by Texas Instruments can work at 600V and 650V. With the new trend to have these cars operating in increasingly higher voltages, such as 800V for the Porsche Taycan and 900V for the Lucid Air, the company may soon develop components that can deal with them.
With smaller onboard chargers and DC-to-DC, electric cars will manage to present less weight, which will make them even more efficient than they naturally are.
Gallium nitride is a wide-bandgap semiconductor with multiple advantages when compared to other materials. It can offer lower on-resistance, which reduces conductance losses and requires less power to drive the circuits. There are also speed operation gains in devices that apply this solution.
It also costs less to produce because gallium is a relatively common element, more abundant than lead. The problem with this metal is that it does not occur naturally and has to be extracted from other minerals, such as coal or bauxite (used to produce aluminum).
Texas Instruments GaN FETs also present a 23-percent lower thermal impedance. According to the company, that “allows engineers to use smaller heat sinks while simplifying thermal designs.” Less heat generation represents electricity is being used more efficiently. The company also contains the higher power losses that could come from the fast switching that GaN FETs permit with what it calls “ideal diode mode.”
For everybody that is not that much into the technical details, the good news is that electric cars can be even more efficient with the help of Texas Instruments’ new GaN FETs. Although we know take transistors for granted, the revolution they brought gives us a good perspective on why these components can keep helping electronics evolve.