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MOSFET with Limited di/dt

Purpose

Dynamic MOSFET model with finite current slopes during turn-on and turn-off

Library

Electrical / Power Semiconductors

Description

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In contrast to the ideal MOSFET model that switches instantaneously, this model includes drain current transients during switching. Thanks to the continuous current decay during turn-off, stray inductances may be connected in series with the device.

This MOSFET model is used to simulate overvoltages produced by parasitic inductances and the reverse recovery effect of diodes. Due to simplified voltage and current transient waveforms, the model is not suited for the simulation of switching losses. The dynamic behavior of this MOSFET model is identical with the one of the IGBT with limited di/dt.


Note 


Parameters

Blocking voltage
Maximum voltage VDSS   in volts (V) that under any conditions should be applied between drain and source.
Continuous drain current
Maximum dc current ID    in amperes (A) that the MOSFET can conduct.
On-resistance
The resistance Ron   of the conducting device, in ohms (_O_  ). The default is 0.
Off-resistance
The resistance Roff    of the blocking device, in ohms (_O_  ). The default is 1e6. This parameter may be set to inf unless multiple MOSFETs are connected in series.
Rise time
Time tr   in seconds between instants when the drain current has risen from 10 % to 90 % of the continuous drain current ID  .
Fall time
Time tf    in seconds between instants when the drain current has dropped from 90 % to 10 % of its initial value along an extrapolated straight line tangent the maximum rate-of-change of the current.
Fall time
Time tf    in seconds between instants when the drain current has dropped from 90 % to 10 % of its initial value along an extrapolated straight line tangent the maximum rate-of-change of the current decay.
Stray inductance
Internal inductance Lσ   in henries (H) measured between the drain and source terminals.
Initial current
The initial current through the component at simulation start, in amperes (A). The default is 0.

Probe Signals

MOSFET voltage
The voltage measured between drain and source.
MOSFET current
The current through the MOSFET flowing from drain to source.
MOSFET conductivity
Conduction state of the internal switch. The signal outputs 0 when the MOSFET is blocking, and 1 when it is conducting.