IEC 60747-6:2025

IEC 60747-6 ®
Edition 4.0 2025-09
INTERNATIONAL
STANDARD
Semiconductor devices -
Part 6: Discrete devices - Thyristors
ICS 31.080.20  ISBN 978-2-8327-0705-0

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CONTENTS
FOREWORD . 6
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 8
3.1 General . 9
3.2 Principal voltages . 9
3.3 Principal currents. 11
3.4 Gate voltages and currents . 12
3.5 Power and energy dissipation . 13
3.5.1 Instantaneous power in a whole period of cycle . 14
3.5.2 Average power dissipation . 15
3.5.3 Energy dissipation. 17
3.6 On-state, recovery and other characteristics . 18
3.6.1 On-state characteristics . 18
3.6.2 Recovery times . 18
3.6.3 Times and rates of rise characteristics gate controlled turn on . 20
3.6.4 Times and rates of rise characterizing gate controlled turn off . 22
3.6.5 Charges . 25
3.7 Mechanical ratings . 26
4 Letter symbols . 26
4.1 General . 26
4.2 Additional general subscripts . 26
4.3 List of letter symbols . 26
5 Essential ratings and characteristics . 29
5.1 General . 29
5.2 Ratings (limiting values) . 29
5.2.1 Storage temperature (T ) . 29
stg
5.2.2 Operating ambient, case, heatsink or junction temperature (T , T , T or
a c s
T ) . 29
vj
5.2.3 Principal voltages. 29
5.2.4 Principal currents . 30
5.2.5 Gate voltages, current and power . 36
5.2.6 Total power dissipation (P ) . 37
tot
5.2.7 Frequency ratings . 37
5.2.8 Mechanical ratings . 37
5.3 Characteristics . 37
5.3.1 General. 37
5.3.2 On-state voltages . 38
5.3.3 On-state characteristics (where appropriate) . 38
5.3.4 Holding current (I ) . 38
H
5.3.5 Latching current (I ) . 39
L
5.3.6 Reverse current (I ) . 39
R
5.3.7 Repetitive peak reverse current (I ) . 39
RRM
5.3.8 Off-state current (I ) . 39
D
5.3.9 Repetitive peak off-state current (I ) . 39
DRM
5.3.10 Gate trigger current (I ) and gate trigger voltage (V ) . 39
GT GT
5.3.11 Gate non-trigger voltage (V ) and gate non-trigger current (I ) . 40
GD GD
5.3.12 Sustaining gate current (I ) (for turn-off thyristors only) . 40
FGsus
5.3.13 Peak turn-off gate current (I ) (for turn-off thyristors only) . 41
RGQM
5.3.14 Peak tail current (I ) (for turn-off thyristors only) . 41
ZM
5.3.15 Characteristic time intervals . 41
5.3.16 Reverse conducting voltage (V ) (for reverse conducting thyristor). 43
RC
5.3.17 Power and energy dissipation . 43
5.3.18 Reverse recovery characteristics (where appropriate) . 45
5.3.19 Thermal resistance. 46
5.3.20 Transient thermal impedance . 46
6 Measuring methods. 47
6.1 General . 47
6.2 Verification of ratings (limiting values). 47
6.2.1 Non-repetitive peak reverse voltage (V ) . 47
RSM
6.2.2 Non-repetitive peak off-state voltage (V ) . 48
DSM
6.2.3 Non-repetitive surge on-state current (I ) . 50
TSM
6.2.4 On-state current ratings of fast switching thyristor . 51
6.2.5 Critical rate of rise of on-state current (di/dt ) . 65
cr
6.2.6 Peak case non-rupture current (I ). 68
RSMC
6.3 Measuring methods for electrical characteristics . 70
6.3.1 On-state voltage (V ). 70
T
6.3.2 Repetitive peak reverse current (I ) . 74
RRM
6.3.3 Latching current (I ) . 75
L
6.3.4 Holding current (I ) . 77
H
6.3.5 Off-state current (I ) . 78
D
6.3.6 Repetitive peak off-state current (I ) . 79
DRM
6.3.7 Gate trigger current (I ) and gate trigger voltage (V ) . 81
GT GT
6.3.8 Gate non-trigger voltage (V ) and gate non-trigger current (I ) . 82
GD GD
6.3.9 Turn-on delay time (t or t ) and turn-on time (t ) . 83
gd d gt
6.3.10 Circuit commutated turn-off time (t ) . 86
q
6.3.11 Critical rate of rise of off-state voltage (dv/dt ) . 89
cr
6.3.12 Critical rate of rise of commutating voltage (dv /dt ) of triac . 91
(com) cr
6.3.13 Recovered charge (Q ) and reverse recovery time (t ) . 98
r rr
6.3.14 Circuit commutated turn-off time (t ) of reverse conducting thyristor . 102
q
6.3.15 Turn off behaviour of turn-off thyristors . 105
6.3.16 Total energy dissipation in a whole period of cycle (for fast switching
thyristor) . 108
6.4 Measuring methods for thermal properties . 109
6.4.1 General. 109
6.4.2 Measurement of the case temperature (T ) . 109
c
6.4.3 Measuring methods for thermal resistance (R ) and transient thermal
th
impedance (Z (t)) . 109
th
6.4.4 Measurement for thermal resistance and transient thermal impedance
(Method A) . 110
6.4.5 Measurement for thermal resistance and transient thermal impedance
(Method B) . 113
6.4.6 Measurement for thermal resistance and transient thermal impedance
(Method C, for turn-off thyristors only) . 126
6.4.7 Measurement for thermal resistance (Method D) . 130
7 Requirements for type tests, routine tests, endurance tests and marking . 134
7.1 Type tests . 134
7.2 Routine tests . 135
7.3 Endurance tests . 135
7.3.1 General. 135
7.3.2 List of endurance tests . 135
7.3.3 Conditions for endurance tests . 137
7.3.4 Acceptance-defining characteristics and acceptance criteria for
endurance tests . 137
7.3.5 Acceptance-defining characteristics and acceptance criteria for
reliability tests . 137
7.4 Measuring and test methods . 137
7.5 Marking . 137
Bibliography . 138

Figure 1 – Peak values of on-state currents . 11
Figure 2 – Partial power (dissipation) of reverse blocking triode thyristor in a whole
period of cycle . 14
Figure 3 – Components of dynamic on-state energy dissipation of reverse blocking
triode thyristor in forward state. 17
Figure 4 – Reverse recovery time of reverse blocking triode thyristor . 19
Figure 5 – Off-state recovery time of reverse conducting triode thyristor . 19
Figure 6 – Circuit commutated turn-off time . 20
Figure 7 – Gate controlled turn-on time . 21
Figure 8 – Gate controlled turn-off time of turn-off thyristor . 23
Figure 9 – Recovered charge . 25
Figure 10 – Peak sinusoidal currents and typical waveform at higher frequencies . 32
Figure 11 – Peak trapezoidal currents and typical waveform at higher frequencies . 34
Figure 12 – Application of gate voltages for thyristors . 36
Figure 13 – Forward gate voltage versus forward gate current . 40
Figure 14 – Examples of current and voltage waveform during turn off of thyristor
under various circuit conditions . 42
Figure 15 – Curves with total energy dissipation E as parameter and sinusoidal
p
current pulse . 44
Figure 16 – Curves with total energy dissipation E as parameter and trapezoidal
p
current pulse . 44
Figure 17 – Recovered charge Q , peak reverse recovery current I and reverse
r rrm
recovery time t (idealized characteristics) . 46
rr
Figure 18 – Circuit diagram for verification of non-repetitive peak reverse voltage . 47
Figure 19 – Circuit diagram for verification of non-repetitive peak off-state voltage . 49
Figure 20 – Circuit diagram for verification of non-repetitive surge on-state current . 50
Figure 21 – Basic circuit diagram and test waveform for verification of sinusoidal on-
state current with reverse voltage applied . 53
Figure 22 – Extended circuit diagram for verification of sinusoidal on-state current with
reverse voltage applied . 54
Figure 23 – Basic circuit diagram and test waveform for verification of sinusoidal on-
state current with reverse voltage suppressed . 56
Figure 25 – Basic circuit diagram and test waveform for verification of trapezoidal on-
state current with reverse voltage applied . 61
Figure 26 – Basic circuit diagram and test waveform for verification of trapezoidal on-
state current with reverse voltage suppressed . 63
Figure 27 – Circuit diagram for verification of critical rate of rise of on-state current . 66
Figure 28 – On-state current waveform for critical rate of rise of on-state current . 67
Figure 29 – Circuit diagram for verification of peak case non-rupture current . 69
Figure 30 – Waveform of reverse current through thyristor . 69
Figure 31 – Circuit diagram for measurement of on-state voltage (DC method) . 71
Figure 32 – Circuit diagram for measurement of on-state voltage (oscilloscope method) . 72
Figure 33 – Graphic representation of on-state voltage versus current characteristic
(oscilloscope method) . 72
Figure 34 – Circuit diagram for measurement of on-state voltage (pulse method) . 73
Figure 35 – Circuit diagram for measurement of peak reverse current . 74
Figure 36 – Circuit diagram for measurement of latching current . 76
Figure 37 – Waveform of latching current . 77
Figure 38 – Circuit diagram for measurement of holding current . 77
Figure 39 – Circuit diagram for measurement of off-state current (DC method) . 79
Figure 40 – Circuit diagram for measurement of peak off-state current . 80
Figure 41 – Circuit diagram for measurement of gate trigger current and voltage . 81
Figure 42 – Circuit diagram for measurement of gate non-trigger voltage and current . 82
Figure 43 – Circuit diagram for measurement of turn-on delay time and turn-on time . 84
Figure 44 – On-state current waveform of thyristor . 85
Figure 45 – Turn-on waveform of thyristor . 86
Figure 46 – Turn-off waveform of thyristor . 87
Figure 47 – Basic circuit diagram for measurement of circuit commutated turn-off time . 88
Figure 48 – Circuit diagram for measurement of critical rate of rise of off-state voltage . 89
Figure 49 – Waveform of linear rate of rise of off-state voltage . 89
Figure 50 – Waveform of exponential rate of rise of off-state voltage . 90
Figure 51 – Circuit diagram for measurement of critical rate of rise of commutating
voltage of low current triac . 92
Figure 52 – Waveform during commutation of low current triac . 93
Figure 53 – Circuit diagram for measurement of critical rate of rise of commutating
voltage of high current triac . 94
Figure 54 – Waveform for measurement of critical rate of rise of commutating voltage
of high current triac with high and low di/dt . 96
Figure 55 – Circuit diagram for measurement of recovered charge and reverse
recovery time (half sinusoidal waveform method) . 98
Figure 56 – Current waveform through thyristor for measurement of recovered charge
and reverse recovery time (half sinusoidal waveform method) . 99
Figure 57 – Circuit diagram for measurement of recovered charge and reverse recover
time (rectangular waveform method) . 101
Figure 58 – Current waveform through thyristor for measurement of recovered charge
and reverse recover time (rectangular waveform method) . 101
Figure 59 – Circuit diagram for measurement of circuit commutated turn-off time of
reverse conducting thyristor . 103
Figure 60 – Current and voltage waveforms of circuit commutated turn-off time of
reverse conducting thyristor . 104
Figure 61 – Circuit diagram for measurement of turn off behaviour of turn-off thyristors . 106
Figure 63 – Basic circuit diagram for measurement of transient thermal impedance
(Method A). 112
Figure 64 – Superposition of reference current pulse on different heating currents . 114
Figure 65 – Waveforms for power dissipation and junction temperature (general case) . 115
Figure 66 – Basic circuit diagram for measurement of thermal resistance (Method B) . 121
Figure 67 – Waveforms for measurement of thermal resistance (Method B) . 122
Figure 68 – Basic circuit diagram for measurement of transient thermal impedance
(Method B). 124
Figure 69 – Waveform for measurement of transient thermal impedance (Method B) . 125
Figure 70 – Basic circuit diagram for measurement of thermal resistance (Method C) . 127
Figure 71 – Waveform for measurement of thermal resistance (Method C) . 128
Figure 72 – Waveform for measurement of transient thermal impedance (Method C) . 129
Figure 73 – Calibration and measurement arrangement for heat flow method. 131

Table 1 – Additional general subscripts. 26
Table 2 – Principal voltages (anode-cathode voltages) . 27
Table 3 – Principal currents (anode currents and cathode currents) . 27
Table 4 – Gate voltages and currents . 28
Table 5 – Characteristic time intervals . 28
Table 6 – Power and energy dissipation . 28
Table 7 – Other characteristics . 29
Table 8 – Minimum type and routine tests for reverse blocking triode thyristor . 135
Table 9 – Conditions for endurance tests . 136
Table 10 – Acceptance-defining characteristics after endurance tests . 137

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Semiconductor devices -
Part 6: Discrete devices - Thyristors

FOREWORD
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IEC 60747-6 has been prepared by subcommittee 47E: Discrete semiconductor devices, of IEC
technical committee 47: Semiconductor devices. It is an International Standard.
This fourth edition cancels and replaces the third edition published in 2016. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the terms and definitions for partial thermal resistance junction-to-case and voltages related
to ratings and characteristics (properties) have been added;
b) Clauses 3, 4, 5, 6 and 7 were amended with some deletions of information no longer in use
and with some necessary additions.
The text of this International Standard is based on the following documents:
Draft Report on voting
47E/863/FDIS 47E/865/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
This International Standard is to be used in conjunction with IEC 60747-1:2006 and its
Amendment 1:2010.
A list of all parts in the IEC 60747 series, published under the general title Semiconductor
devices, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
1 Scope
This part of IEC 60747 specifies product specific standards for terminology, letter symbols,
essential ratings and characteristics (properties), measuring and test methods, requirements
for type tests, routine tests, endurance tests and marking for the following discrete
semiconductor devices:
– reverse blocking triode thyristors;
– reverse conducting (triode) thyristors;
– bidirectional triode thyristors (triacs);
– turn-off thyristors.
If no ambiguity is likely to result, any of the above will be referred to as thyristors.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60050-521, International Electrotechnical Vocabulary (IEV) - Part 521: Semiconductor
devices and integrated circuits, available at http://www.electropedia.org
IEC 60747-1:2006, Semiconductor devices - Part 1: General
IEC 60747-1:2006/AMD1:2010
IEC 60749-23, Semiconductor devices - Mechanical and climatic test methods - Part 23: High
temperature operating life
IEC 60749-25, Semiconductor devices - Mechanical and climatic test methods - Part 25:
Temperature cycling
IEC 60749-34, Semiconductor devices - Mechanical and climatic test methods - Part 34: Power
cycling
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60747-1, in
IEC 60050-521 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1 General
3.1.1
reverse blocking triode thyristor
three-terminal thyristor which for negative anode voltage does not switch, but exhibits a reverse
blocking state
Note 1 to entry: The P-gate thyristor (see IEC 60050-521:2002, 521-04-69) and the N-gate thyristor (see
IEC 60050-521:2002, 521-04-70) are two kinds of reverse blocking triode thyristors.
[SOURCE: IEC 60050-521:2002, 521-04-63, modified – Note 1 to entry has been added.]
3.1.2
bidirectional triode thyristor
triac
three-terminal thyristor having substantially the same switching behaviour in the first and third
quadrants of the current-voltage characteristic
[SOURCE: IEC 60050-521:2002, 521-04-67]
3.1.3
turn-off thyristor
thyristor which can be switched from the on-state to the off-state and vice versa by applying
control signals of appropriate polarity to the gate terminal
EXAMPLE Gate turn-off thyristor (GTO), gate-commutated thyristor (GCT) and integrated gate-commutated
thyristor (IGCT).
[SOURCE: IEC 60050-521:2002, 521-04-68, modified – The example has been added.]
3.1.4
reverse conducting triode thyristor
three-terminal thyristor that conducts large currents in the reverse direction at reverse voltages
comparable in magnitude to the forward on-state voltage
[SOURCE: IEC 60050-521:2002, 521-04-65, modified – The wording “which for negative anode
voltage does not switch and” has been deleted and the words “at voltages” replaced with “in
the reverse direction at reverse voltages”.]
3.2 Principal voltages
3.2.1
repetitive peak reverse voltage
V
RRM
maximum instantaneous value of the reverse voltage, including all repetitive transient voltages,
but excluding all non-repetitive transient voltages
Note 1 to entry: The repetitive voltage is usually a function of the circuit and increases the power loss of the device.
A non-repetitive transient voltage is usually due to an external cause, and it is assumed that its effect has completely
disappeared before the next transient arrives.
3.2.2
non-repetitive peak reverse voltage
peak transient reverse voltage
V
RSM
maximum instantaneous value of any non-repetitive transient reverse voltage
Note 1 to entry: The repetitive voltage is usually a function of the circuit and increases the power loss of the device.
A non-repetitive transient voltage is usually due to an external cause, and it is assumed that its effect has completely
disappeared before the next transient arrives.
3.2.3
off-state voltage
V
D
anode, principal or thyristor voltage while the thyristor is in the off state
3.2.4
repetitive peak off-state voltage
V
DRM
maximum instantaneous value of the off-state voltage, including all repetitive transient voltages,
but excluding all non-repetitive transient voltages
Note 1 to entry: The repetitive voltage is usually a function of the circuit and increases the power loss of the device.
A non-repetitive transient voltage is usually due to an external cause, and it is assumed that its effect has completely
disappeared before the next transient arrives.
3.2.5
non-repetitive peak off-state voltage
peak transient off-state voltage
V
DSM
maximum instantaneous value of any non-repetitive transient off-state voltage
Note 1 to entry: The repetitive voltage is usually a function of the circuit and increases the power loss of the device.
A non-repetitive transient voltage is usually due to an external cause, and it is assumed that its effect has completely
disappeared before the next transient arrives.
3.2.6
direct off-state voltage
V
D(D)
off-state voltage that is independent of time or in which the changes are so small that they can
be neglected
3.2.7
on-state voltage
V
T
anode, principal or thyristor voltage which results from the flow of current while the thyristor is
in the on state
3.2.8
peak on-state voltage
V
TM
anode, principal or thyristor voltage which results from the specified peak on-state current
3.2.9
critical rate of rise of commutating voltage
dv /dt
(com) cr
maximum value of the rate of rise of off-state voltage,
immediately following reverse current conduction, that will not cause switching from the off state
to the on state
Note 1 to entry: The measuring method for the rate of rise of commutating voltage is to be specified.
Note 2 to entry: If no ambiguity is likely to result, the shorter expression of the letter symbol “dv /dt” may be
(com)
used.
3.2.10
critical rate of rise of commutating voltage
critical rate of rise of re-applied off-state voltage
dv /dt
(com) cr
maximum value of the rate of rise of off-state voltage,
immediately following on-state current conduction in the opposite direction, that will not cause
switching from the off state to the on state
Note 1 to entry: The measuring method for the rate of rise of commutating voltage is to be specified.
Note 2 to entry: If no ambiguity is likely to result, the shorter expression of the letter symbol “dv /dt” may be
(com)
used.
3.3 Principal currents
3.3.1
non-repetitive surge on-state current
I
TSM
on-state current pulse with short duration and specified waveform
SEE: Figure 1.
Note 1 to entry: Occurrence of the non-repetitive surge on-state current causes or would cause the maximum rated
virtual junction temperature to be exceeded, but which is assumed to occur rarely and with a limited number of such
occurrences during the service life of the device and to be a consequence of unusual circuit conditions (e.g., a fault).

Figure 1 – Peak values of on-state currents
3.3.2
I t value
integral of the square of non-repetitive surge on-state current over the duration of the current
surge
3.3.3
repetitive peak on-state current
I
TRM
peak value of the on-state current, including all repetitive transient currents
SEE: Figure 1.
3.3.4
overload on-state current
I
T(OV)
on-state current whose continuous application would cause the maximum rated virtual junction
temperature to be exceeded
SEE: Figure 1.
3.3.5
overload reverse conducting current
I
RC(OV)
reverse conducting current whose continuous application
would cause the maximum rated virtual junction temperature to be exceeded
3.3.6
non-repetitive surge reverse current
I
RCSM
non-repetitive peak reverse current pulse with short
duration and specified waveform
3.3.7
tail current
i
Z
anode current flowing during the tail time
Note 1 to entry: Refer to 3.6.4.
3.3.8
peak tail current
I
ZM
peak value of the tail current that occurs shortly after the beginning of the
tail time
Note 1 to entry: Refer to 3.6.4.
3.3.9
peak case non-rupture current
I
RSMC
peak value of reverse current that will not cause bursting of the case or the emission of a plasma
beam under specified conditions, waveform and duration of the current as well as temperature
Note 1 to entry: This definition implies that a fine crack in the case could also be found in a device subjected to the
peak case non-rupture current, provided that no plasma beam was emitted. Parts of the case shall not break away,
nor shall the device melt externally or burst into flames.
3.4 Gate voltages and currents
3.4.1
on-state gate bias current
I
FGB
forward gate current flowing after the thyristor has been turned on
3.4.2
sustaining gate current
I
FGsus
minimum forward gate current required ensuring that, if the anode current
drops below the value required to maintain all the subdivided cathode areas in conduction, they
will all return to conduction when the anode current is increased again
3.4.3
off-state gate bias voltage
V
RGB
reverse gate voltage applied after the thyristor has been turned off
3.4.4
turn-off gate voltage
V
RGQ
reverse gate voltage during the time interval within which the thyristor is
turning off
3.4.5
turn-off gate current
I
RGQ
reverse gate current during the time interval within which thyristor is turning
off
3.4.6
peak turn-off gate voltage
V
RGQM
peak value of the turn-off gate voltage at the end of its rapid rise after the
peak turn-off gate current has been reached
3.4.7
peak turn-off gate current
I
RGQM
peak value of the reverse gate current reached at the end of its rapid rise in
the beginning of the turn off process
Note 1 to entry: Specifications refer to the minimum value of the peak turn-off gate current that the gate turn-off
pulse source is capable of supplying as a function of the peak on-state current to be switched off under specified
conditions.
3.4.8
turn-off gate bias voltage
V
RGQB
essentially constant value of the turn-off gate voltage that occurs towards
the end of the turn off process, in the case where the gate control circuit supports this process
by maintaining the turn-off gate voltage at a value that is higher than the off-state gate bias
voltage
3.4.9
turn-off gate bias current
I
RGQB
reverse gate current associated with the turn-off gate bias voltage
3.5 Power and energy dissipation
NOTE All definitions are written in terms of triode thyristors. Where appropriate, they apply also to diode thyristors.
All definitions for power and power dissipation refer, if not otherwise specified, to the product of anode or principal
current and anode or principal voltage. The definitions are general. It is not considered that the beginning and ending
of the particular time interval are necessary to be identified in order to make specifications for the derived
characteristics “average partial power dissipation” and “partial energy dissipation” meaningful. However, guidance
for the specification of these time intervals is given in the relevant notes.
3.5.1 Instantaneous power in a whole period of cycle
3.5.1.1
reverse power
P
R
power while the thyristor is in the reverse blocking state
Note 1 to entry: If not otherwise specified, the term refers to the power in the time interval between the ending of
the turn-off time and the change from the reverse blocking state to the off state (either I = 0 or V = 0) (see Figure 2).

Key
P off-state power P on-state power
D T
P turn-off power P turn-on power
RQ TT
P reverse power
R
Figure 2 – Partial power (dissipation) of reverse blocking triode thyristor
in a whole period of cycle
3.5.1.2
off-state power
P
D
power while the thyristor is in the off state
Note 1 to entry: If
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