Power Function Power MOSFET SPICE model

Author: Andre Adrian
Version: 8.Aug.2013

Introduction

The trade magazin High Frequency Electronics did publish my article "A power MOSFET SPICE model with built-in model generator" in the August 2013 version. The article closes with the sentence "The LTSpice model files can be found at http://www.andreadrian.de/pfpm". Welcome to this page!

Download of Power Function model LTSpice files

The files are compressed into a ZIP file. The files are in the folder pfpm_V1_2. Click on this pfpm_V1_2 link to down load the ZIP file.

Components of the PFPM model

The components of the radio frequency large-signal model use SPICE standard components and hierarchical components (schematics). The gate resistor Rg, the bond wire inductances Lg, Ld, Ls and the capacitor Cgs are standard components. The component values can be changed as usual. The capacities of Cds and Cgd are voltage dependent. The body diode Dds has a strictly monotonic forward current to forward voltage characteristics. The MOSFET component realizes the transfer function and output function.

Figure 1 - Radio frequency SPICE model of a power MOSFET

Body diode SPICE model

The diode model is very simple. The backward current is always 0. The forward voltage is not temperature dependent. Breakdown of the diode is not simulated. If a power MOSFET is used in linear mode as RF amplifier, soft-switching converter or RF oscillator the body diode should not become active (have forward current). The body diode model information is forwarded via parameters from the PFPM schematic to the body diode schematic.

Figure 2 - SPICE model of the body diode

Voltage dependent capacity (varactor) SPICE model

The SPICE component name is VDCAP for Voltage Dependent CAPacity.

Figure 3 - SPICE model of a varactor

Direct current PFPM MOSFET model

The output function defines the direct current amplification of the power MOSFET.

Figure 4 - SPICE model of the MOSFET outpunt function

Huth Kühn (Hartley) oscillator

Version 1.1 of the oscillator circuit is presented. The modifications are:

The potentiometer voltage is Zener diode stabilized.
The bias voltage transistor can handle more current.
The LC circuit electrical elements are arranged in a dashed lines box. These elements should be placed close to each other.

Figure 5 - Hartley (Huth Kühn) oscillator.