Rugged MOSFETs Bring More Control and Reliability to Automotive Systems

While production EVs have been around since the early 2010s, modern EVs are undergoing a transition to higher voltages, often exceeding 500 V. As a result, semiconductor manufacturers are creating MOSFETs that can withstand high voltage and currents, increase efficiency, and minimize costs.

Littelfuse, Alpha and Omega Semiconductor, and Magnachip offer MOSFETs that target these three goals for automotive applications. 

 

Littelfuse Drops Drain-to-Source On-Resistance

Littelfuse, a leading provider of power electrical components and sensors, announced the release of the 500 V, 2 A IXTY2P50PA (datasheet linked), described as the first “PolarP P-channel power MOSFET” that is AEC-Q101 qualified. The Littelfuse Polar series aims to minimize operating losses by lowering the drain-to-source on-resistance of the MOSFET.

 

Littelfuse’s IXTY2P50PA is optimized for high-voltage applications. Image used courtesy of Littelfuse

 

According to Littelfuse, the IXTY2P50PA has a drain-to-source on-resistance of 4.2 Ω. This results in lower conduction losses at higher currents, because less energy is dissipated as heat. The IXTY2P50PA also has a high avalanche rating, making it suitable for high-voltage applications. The avalanche rating indicates the maximum tolerable reverse voltage that the MOSFET can withstand when it exceeds the maximum allowable breakdown voltage.

 

Alpha and Omega Shrinks Down MOSFET Packaging

Manufacturers are not only improving MOSFETs in intrinsic gate-level performance but also in packaging. Package size is especially important for two and three-wheeler electric vehicles to reduce overall board size and cut costs. In December, Alpha and Omega Semiconductor announced AOTL66810Q and AOTL66910Q, 80-V and 100-V MOSFETs, respectively.

 

Alpha and Omega's TOLL package technology is specially designed for two- and three-wheelers and other light vehicles. Image (modified) used courtesy of Alpha and Omega Semiconductor

 

These MOSFETs use automotive-grade TO-leadless (TOLL) packaging that can withstand over 400 A of continuous drain current at room temperature. The company says the packaging shrinks the device's footprint by 30% compared to conventional solutions. Leadless packaging saves space by keeping contact points underneath the device instead of on the perimeter.

Alpha and Omega claims its clip technology helps to achieve a high in-rush current rating and low package resistance and inductance. With these features, Alpha and Omega's clip technology is said to boost EMI performance compared to other TOLL packages that use standard wire-bonding technology. Because of the device's high current and low ohmic features, designers can cut the number of parallel MOSFETs they use in high-current designs. 

 

Magnachip Targets Low-Voltage Applications

Magnachip, a South Korean firm specializing in analog and mixed-signal devices, is also seeking to shrink board footprint with the mass production of its new 30-V MXT LV MOSFET. MXT LV stands for Magnachip eXtreme trench low voltage and refers to the company's portfolio of 12~40 V trench MOSFETs. This 30-V iteration has a low drain-to-source resistance in a compact ruggedized package size of 3.3 mm x 3.3 mm. Unlike the other MOSFETs, however, the Magnachip AMDV030N150URH targets lower-voltage applications in vehicles such as power steering systems. 

 

Magnachip's 30-V MXT LV MOSFET targets the electronic control units of electric power steering systems, road switches, and switching power supply units. Image (modified) used courtesy of Magnachip

 

In addition to its wide operating junction temperature range of -55°C to 175°C, the new device integrates a rugged trench MOSFET structure in a thick gate oxide. This improves the device's switching characteristics and lowers its resistance, thereby reducing noise and enhancing system performance and power efficiency.

 

High-Yield Improvements to MOSFETs

As demand for electric vehicles (EVs), including two-wheeler EVs, has grown over the past decade, manufacturers are developing components that can withstand the harsh electrical and environmental requirements of modern automotive systems. MOSFETs are a fruitful area of automotive innovation because they act as voltage-controlled switches and are often used in EV traction inverters. Developers like Littelfuse, Alpha and Omega Semiconductor, and Magnachip demonstrate how power efficiency, drain-to-source on-resistance, and package size are of the utmost importance in this next wave of devices.