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Behavioral model of a diode with reverse recovery.
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This component is a behavioral model of a diode which reproduces the effect of reverse recovery. This effect can be observed when a forward biased diode is rapidly turned off. It takes some time until the excess charge stored in the diode during conduction is removed. During this time the diode represents a short circuit instead of an open circuit, and a negative current can flow through the diode. The diode finally turns off when the charge is swept out by the reverse current and lost by internal recombination.
The following figure illustrates the relationship between the diode parameters and
the turn-off current waveform. and
denote the continuous forward
current and the rated turn-off current slope under test conditions. The turn-off time
is defined as the period between the zero-crossing of the current and the instant
when it becomes equal to 10% of the maximum reverse current
. The reverse
recovery charge is denoted
. Only two out of the three parameters
,
, and
need to be specified since they are linked geometrically. The
remaining parameter should be set to 0. If all three parameters are given,
is
ignored.
The equivalent circuit of the diode model is shown below. It is composed of a resistance, and inductance, and a controlled current source which is linearly dependent on the inductor voltage. The values of these internal elements are automatically calculated from the diode parameters.