# Piecewise Linear MOSFET

## Description

This MOSFET model is developped with two key objectives:

**Accuracy and Computational Efficiency**: The model accurately simulates both switching and static behaviors of MOSFETs and is optimized for fast simulation.**Robustness and Characterization**: It is designed to be robust and can be easily characterized using standard datasheet.

This MOSFET model incorporates:

- Three nonlinear capacitances C_{GD} , C_{GS} , and C_{DS} characterized by Capacitance- V_{DS} matrices, modeling C_{ISS} , C_{OSS} , and C_{RRS} respectively.
- A PWL Diode representing the MOSFET body diode, characterized by a Voltage-Current data matrix.
- An internal piecewise linear MOSFET model using 3D Triangular meshing for output and transfer characteristics (details below).
- An internal gate resistance R_G .

### Capacitances

The capacitances are calculated as follows:

Capacitance Consistency

It is recommended that all three capacitances share the same V_{DS} values. If not, interpolation is used to calculate missing V_{DS} values.

Capacitance Options

Alternatively, a single capacitance value can be used to model a V_{DS} -independent capacitance.

### Body Diode

To accurately model the diode's off state, include at least one data point with a negative voltage in the characteristics matrix. In most cases, modeling avalanche breakdown is unnecessary.

### MOSFET Equations

The internal MOSFET model employs the following drain current equations:

Optimization techniques are employed to derive V_{th} , \lambda , and K from the output and transfer characteristics data. DIRECT (DIviding RECTangles) algorithm is used for this optimization, as described in:

- D. R. Jones, C. D. Pertunen, and B. E. Stuckmann, "Lipschitzian optimization without the lipschitz constant," J. Optimization Theory and Applications, vol. 79, p. 157 (1993).

### Beta Status

The Piecewise Linear MOSFET model is currently in Beta. It is not advised for production use. For issues, contact support@simba.io or file an issue on Github. A list of known issues can be found here.

## Library

Electrical > Semiconductors

## Pins

Name | Description |
---|---|

Drain | Drain |

Source | Source |

Gate | Gate (Control Input) |

## Parameters

Name | Description |
---|---|

Rg | Gate Internal Resistance value, in Ohm |

VgsIdMatrix | Transfer Characteristic |

VgsIdMatrix_Vds | Transfer Characteristics Vds |

VdsIdMatrix | Output Characteristics |

VdsIdMatrix_Vgs | Output Characteristics Vgs |

Ciss | Input Capacitance, in F |

Coss | Output Capacitance |

Crss | Reverse Transfer Capacitance |

Vsd_Is_BodyDiodeMatrix | Source Drain current vs Source-Drain Voltage (Body Diode) |