Tutorial for Characterizing a Power MOSFET (Average)

Use the power MOSFET Device Characterization Wizard to parameterize an average power MOSFET model to match both the DC and switching energies of a device using information from the manufacturer's data sheet. The information available in the data sheet limits the accuracy of the parameterized power MOSFET model. For example, if the data sheet does not provide a device's transfer characteristics, the accuracy of the gate-voltage dependence of the output will be reduced.

The power MOSFET device characterization tool performs the following tasks:

• Static parameter fitting

The static parameter fitting works by using the following user-supplied information to determine the value of static core model parameters:

• The MOSFET’s transfer characteristic.
• Its output characteristic.
• Its thermal characteristic.
• The forward and thermal characteristics of the MOSFET’s source to drain diode, if used.
• Energy Characteristics

The average power MOSFET model is a static model capable of switching loss estimation. Swithching energies are interpolated/extrapolated according to working conditions at the time of each switching. The parameter extraction uses additional user-supplied information—namely, the t turn-on energy, turn-off energy, and reverse recovery energy—to determine the values of the MOSFET’s switching energy related parameters. The datasheet test conditions as supplied by the manufacturer serve as the nominal and alternative working conditions. You must input into the device characterization tool data at multiple working points to correctly characterize the device.

• Validation

When the static parameter fitting and switching energy extraction are complete, the device characterization tool uses the full set of parameters to perform a validation based on the provided test conditions.

The wizard can characterize a wide array of power MOSFETs. The available information varies from vendor to vendor, and even between devices from the same vendor. If you have any additional questions, contact Ansys support.

Related Topics 

Preliminary Considerations Using Power MOSFET (Average) Data Sheet Information

Using the Device Characterization Wizard for a Power MOSFET (Average)