Characterization of dynamic SOA of power MOSFETs limited by electrothermal breakdown

Power DMOS dynamic safe operating area (SOA) limited by electrothermal breakdown is characterized. In a systematic, model-based approach, the original power-to-failure measurement data taken on drivers of various area are translated into iso-failure time lines in the I_ds-V_ds plane constituting the SOA. First, the failure data are analyzed in the framework of a well-established analytical thermal model, the parameters of which are determined in an original and consistent way. Then, the iso-failure time lines are constructed by normalization of the original failure data with the help of the model. They do not coincide with iso-power lines as a result of electrothermal coupling. The trade-off between specific on-resistance and thermal SOA is also demonstrated.