Alpha and Omega Semiconductor Debuts a 1200V SiC MOSFET for EVs

Alpha and Omega’s (AOS) 1200-volt AOM033V120X2Q, employing the company’s αSiC MOSFET technology, is aimed at EV manufacturers who are increasingly implementing 800 volt electrical systems to save weight and space. AOS’ new devices meet tough automotive requirements by exceeding the switching performance and efficiency afforded by the old school silicon devices previously employed.

The AOM033V120X2Q, a 1200V αSiC Power MOSFET. Image courtesy of Datasheet

 

The AOM033V120X2Q is based on AOS’ second generation αSiC MOSFET platform. It’s available in a four lead, TO-247-4L package, with an additional sense (kelvin) lead. The fourth lead serves to reduce the effects of package inductance and enables the device to operate at a higher switching frequency. When compared to standard packaging, this arrangement affords as much as a 75% reduction in switching losses.

AOS’ αSiC MOSFETs feature a very low rate of increase in for its on-resistance with temperature, with low derating even up to its rated 175°C. This serves to lessen power losses and serves to further improve efficiency.

 

Wide Compatibility

The low 15 volt gate driving voltage allows for the widest compatibility with the standard gate drivers on the market today. This allows for the easy incorporation of the AOM033V120X2Q into many varied system designs. 

As stated by David Sheridan, Sr. Director of Wide Bandgap Products at AOS, “For the continued transformation of transportation to EV technology, vehicle manufacturers are making efforts to increase range and reduce the time spent charging. With our release of these automotive-qualified 1200V αSiC MOSFETs, AOS can provide designers with next-generation semiconductor technology to increase these efficiency targets. Our customers have selected our technology due to the combination of product performance, reliability, and volume capable supply chain,” 

 

Power and Thermal Specifications 

The AOM033V120X2Q can handle continuous drain currents of 68 and 48 amps at 25 and 100°C, respectively. The maximum pulsed gain current is 120 amps, and Single Pulse Avalanche Energy  (EAS) 1,000 mJ. The device can dissipate up to 300 watts.

Maximum junction to ambient thermal resistance (RθJA) is 40 °C/W.  For maximum Junction-to-Case  (RθJC) thermal resistance, the figure is 0.5 °C/W.

 

Switching Performance

Switching performance can be thought of being dependent on the time it takes to make voltage changes across the MOSFET’s assorted internal capacitances. There are many factors involved, and this is definitely a case of one sized Does Not Fit All. The designer must scrutinize prospect data sheets to find the best fit for the particular application. Here are some oft-repeated parameters, and the typical values specified for the AOM033V120X2Q.

• Input capacitance (Ciss): 2908 pF 
• Output capacitance (Coss): 128 pF
• Reverse transfer capacitance (Crss): 9.9 pF
• Body Diode Reverse Recovery Charge (Qrr): 226 nC
• Total gate charge (Qg): 104 nC

 

Of course, there are far too many specifications to be listed here. A complete listing can be found in the AOM033V120X2Q datasheet.

 

Expansion of AOS’ αSiC MOSFET portfolio 

In the AOM033V120X2Q product announcement, AOS states that later this year, the company plans to introduce new αSiC MOSFET products. These innovations will revolve around variations in packaging and on-resistance options.

 

Applications

• On-board chargers for EVs
• Motor drive inverters
• Off-board charging

 

Physical Considerations

• The AOM033V120X2Q operates at temperatures up to 175℃

 

Regulatory Certifications

• AEQ-101
• PAPP (Production part approval process) capable