Diode with Reverse Recovery
Purpose
Dynamic diode model with reverse recovery
Library
Electrical / Power Semiconductors
Description
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.
Note
- Due to the small time-constant introduced by the turn-off transient a stiff solver is recommended for this device model.
- If multiple diodes are connected in series the off-resistance may not be infinite.
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.
Parameters
- Forward voltage
- Additional dc voltage
in volts (V) between anode and cathode when the diode is conducting. The default is 0.
- On-resistance
- The resistance
of the conducting device, in ohms (
). The default is 0.
- Off-resistance
- The resistance
of the blocking device, in ohms (
). The default is 1e6. This parameter may be set to inf unless multiple diodes are connected in series.
- Continuous forward current
- The continuous forward current
under test conditions.
- Current slope at turn-off
- The turn-off current slope
under test conditions.
- Reverse recovery time
- The turn-off time
under test conditions.
- Peak recovery current
- The absolute peak value of the reverse current
under test conditions.
- Reverse recovery charge
- The reverse recovery charge
under test conditions. If both
and
are specified, this parameter is ignored.
- Lrr
- This inductance acts as a probe measuring the
. It should be set to a very small value. The default is 10e-10.
Probe Signals
- Diode voltage
- The voltage measured between anode and cathode.
- Diode current
- The current through the diode flowing from anode to cathode.
- Diode conductivity
- Conduction state of the internal switch. The signal outputs 0 when the diode is blocking, and 1 when it is conducting.
References
- A. Courtay, "MAST power diode and thyristor models including automatic parameter extraction", SABER User Group Meeting Brighton, UK, Sept. 1995.