AN EQUIVALENT-CIRCUIT CHARACTERIZATION OF POWER MOSFETS ACCOUNTING FOR HIGH-FIELD AND HIGH-FREQUENCY EFFECTS

An equivalent circuit model for analyzing the AC characteristics of po wer VDMOS transistors is presented. The model accounts for high field and saturation effects. This is achieved by incorporating dependent vo ltage and current sources in the device model. Results are given for t he AC characteristics of a POLYFET F2001 Power VDMOSFET rated with a d rain current of 1.4A, power out of 2.5W at 1 GHz. The linear, quasi-sa turation and saturation regions of the IV characteristics are accounte d for in the analysis. The small signal device parasitics are extracte d through s-parameter methods. The s-parameter results were used to ex tract the frequency dependent parasitics including parasitic capacitan ces, inductances and transconductances.