Incremental improvements deliver significant benefits to high-power automotive applications

Modern vehicles are employing more electronics than ever before to make them more efficient and ultimately, safer. Improved efficiency not only reduces vehicle running costs but also means less heat is generated in the on-board electronic systems. This, in turn, means those systems can operate with less cooling, allowing them to become smaller. Smaller systems are, by definition, lighter - which also has a positive impact on the efficiency of the vehicle.

Consumers see the benefit of enhanced in-vehicle technology in terms of greater functionality in areas such as comfort, infotainment, security, connectivity and driver assistance systems. The increased efficiency has a particular impact on EVs and HEVs that will travel further on a single charge. Yet, seemingly simple changes and small improvements in semiconductor components are behind these efficiency improvements.

Some of the most important components in modern vehicles are the MOSFETs that switch the power needed for pumps and fans to turn, seats to move or locks to operate.

Toshiba has developed a novel copper connector technology for key MOSFETs that are used in automotive applications. This is used in the unique TO-220SM(W) SMD power package that measures 10mm x 13mm and incorporates a 3x wider and shorter source pin than a conventional D2PAK package.

Due to the improved source pin dimensions, package resistance is reduced by about 0.15mΩ. Compare, for example, Toshiba’s TK1R4F04PB 40V, 1.35mΩ (max) MOSFET in the TO-220SM(W) package with the TK1R5R04PB 40V, 1.5mΩ (max) MOSFET in D2PAK+. While both use the same chip within the package, the on-resistance (R_DS(ON)) of TK1R4F04PB is 0.15mΩ lower than that of the TK1R5R04PB.

These extremely low values would simply not be possible without the combination of Toshiba’s established copper connecter technology, its unique TO-220SW(W) package technology, and a highly advanced wafer process.

In automotive applications where currents can be very large (and potential losses, therefore, significant) improvements of just 0.15mΩ in R_DS(ON are very significant.

A comprehensive white paper describing how the latest high-performance MOSFETs are enabling automotive power systems has been published by Toshiba. For more information visit