IEC 60747-7:2010

IEC 60747-7 ®
Edition 3.0 2010-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Semiconductor devices – Discrete devices –
Part 7: Bipolar transistors
Dispositifs à semiconducteurs – Dispositifs discrets –
Partie 7: Transistors bipolaires

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IEC 60747-7 ®
Edition 3.0 2010-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Semiconductor devices – Discrete devices –
Part 7: Bipolar transistors
Dispositifs à semiconducteurs – Dispositifs discrets –
Partie 7: Transistors bipolaires

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XD
CODE PRIX
ICS 31.080.30 ISBN 978-2-88912-311-7
– 2 – 60747-7 Ó IEC:2010
CONTENTS
FOREW ORD . 6
1 Sc o pe . 8
2 Normative references . 8
3 Terms and definitions . 8
3.1 Specific functional regions . 8
3.2 Resistor biased transistor . 9
3.3 Terms related to ratings and characteristics . 10
4 Letter symbols . 13
4.1 General . 13
4.2 Additional subscripts . 13
4.3 List of letter symbols . 13
4.3.1 General . 13
4.3.2 Voltages . 14
4.3.3 Currents . 15
4.3.4 Powers. 15
4.3.5 Electrical parameters . 15
4.3.6 Frequency parameters . 19
4.3.7 Switching parameters . 20
4.3.8 Energies . 21
4.3.9 Sundry quantities . 21
4.3.10 Matched-pair bipolar transistors . 22
4.3.11 Resistor biased transistor. 22
5 Essential ratings and characteristics . 22
5.1 General . 22
5.2 Small signal transistors . 22
5.2.1 Ratings (limiting values) . 22
5.2.2 Characteristics . 23
5.3 Linear power transistors . 24
5.3.1 Ratings (limiting values) . 24
5.3.2 Characteristics . 25
5.4 High-frequency power transistors for amplifier and oscillator applications . 26
5.4.1 Ratings (limiting values) . 26
5.4.2 Characteristics . 27
5.5 Switching transistors . 29
5.5.1 Ratings (limiting values) . 29
5.5.2 Characteristics . 31
5.6 Resistor biased transistors . 33
5.6.1 Ratings . 33
5.6.2 Characteristics . 34
6 Measuring methods . 34
6.1 General . 34
6.2 Verification of ratings (limiting values) . 35
6.2.1 Acceptance criteria . 35
6.2.2 Collector current . 35
6.2.3 Peak collector current . 36
6.2.4 Base current . 36

60747-7 Ó IEC:2010 – 3 –
6.2.5 Peak base current . 37
6.2.6 Collector-base voltage . 38
6.2.7 Collector-emitter voltage, output voltage . 39
6.2.8 Emitter-base voltage, Input voltage . 39
6.2.9 Safe operating area (SOA) . 40
6.2.10 Output current (I ) . 43
O
6.2.11 Collector-emitter sustaining voltage . 44
6.3 Methods of measurement . 46
6.3.1 Turn-on time intervals and turn-on energy with inductive road . 46
6.3.2 Turn-off time intervals and turn-off energy with inductive road . 47
6.3.3 Collector-emitter cut-off currents (d.c. method) . 49
6.3.4 Collector-base cut-off current (d.c. method) . 49
6.3.5 Emitter-base cut-off current (d.c. method) . 50
6.3.6 Collector-emitter saturation voltage . 50
6.3.7 Base-emitter saturation voltage . 52
6.3.8 Base-emitter voltage (d.c. method) . 53
6.3.9 Capacitances . 54
6.3.10 Hybrid parameters (small-signal and large-signal) . 57
6.3.11 Thermal resistance . 64
6.3.12 Switching times with resistive road . 69
6.3.13 High-frequency parameters (f , y.e, s.). 71
T
6.3.14 Noise (F) . 81
6.3.15 Measuring methods for matched-pair bipolar transistors . 87
6.3.16 Measuring Methods for resistor biased transistors . 90
7 Acceptance and reliability . 94
7.1 General requirements . 94
7.2 Specific requirements . 94
7.2.1 List of endurance tests. 94
7.2.2 Conditions for endurance tests . 94
7.2.3 Acceptance-defining characteristics and acceptance criteria for
reliability tests . 94
7.3 Endurance and reliability test methods . 95
7.3.1 High temperature blocking (HTRB) . 95
7.3.2 Intermittent operating life . 96
7.4 Type tests and routine tests . 97
7.4.1 Type tests . 97
7.4.2 Routine tests . 97
Annex A (informative) Determination of the SOA . 99

Figure 1 – Resistor biased transistor graphical symbol . 9
Figure 2 – Modified hybrid p equivalent circuit . 19
Figure 3 – Test circuit for collector current . 35
Figure 4 – Test circuit for peak collector current . 36
Figure 5 – Test circuit for base current . 37
Figure 6 – Test circuit for peak base current. 37
Figure 7 – Circuit for testing the collector-base voltage V , V , V , V . 38
CBO CBS CBR CBX
Figure 8 – Circuit for testing the collector-emitter voltage V , V , V , V V . 39
CEO CES CER CEX, O
Figure 9 – Circuit for testing the emitter-base voltages V and input voltage V . 40
EBO I
– 4 – 60747-7 Ó IEC:2010
Figure 10 – Test circuit of reverse bias safe operating area (RBSOA) . 40
Figure 11 – Waveforms and curves for RBSOA . 41
Figure 12 – Circuit for testing safe operating pulse duration at load short circuit
(SCSOA) . 42
Figure 13 – Waveforms of base current I , collector current I and voltage V during
B C CE
load short circuit condition SCSOA . 43
Figure 14 – Circuit diagram for verifying the output current I . 44
O
Figure 15 – Basic circuit for the measurement of the collector-emitter sustaining
voltage . 44
Figure 16 – I versus V characteristic . 45
C CE
Figure 17 – Circuit diagram and waveforms . 47
Figure 18 – Waveforms during turn-off intervals . 48
Figure 19 – Basic circuit for the measurement of collector-emitter cut-off currents. 49
Figure 20 – Basic circuit for the measurement of the collector-emitter saturation
voltage (d.c. method) . 50
Figure 21 – Basic circuit for the measurement of the collector-emitter saturation
voltage (pulse method) . 51
Figure 22 – Basic circuit for the measurement of the base-emitter saturation voltage
(d.c. method) . 52
Figure 23 – Basic circuit for the measurement of the base-emitter saturation voltage
(pulse methods) . 53
Figure 24 – Base circuit for the measurement of base-emitter voltage (d.c. method) . 54
Figure 25 – Basic circuit for the measurement of the common-base output capacitance
using a two-terminal bridge. 55
Figure 26 – Basic circuit for the measurement of C using a three-terminal bridge . 56
CB
Figure 27 – Basic circuit for the measurement of C using a three-terminal bridge . 57
cb
Figure 28 – Basic circuit for the measurement of h and h . 58
11e 21e
Figure 29 – Basic circuit for the measurement of h . 59
12e
Figure 30 – Basic circuit for the measurement of h . 61
22e
Figure 31 – Basic circuit for the measurement of h . 62
22b
Figure 32 – Basic circuit for the measurement of h . 63
21E
Figure 33 – Basic test circuit for measuring the thermal resistance of NPN transistors . 66
Figure 34 – Emitter current (I ) versus emitter-base voltage (V ) for the junction
E EB
(1) (2)
temperatures T and T . 66
j j
Figure 35 – I and V change with time . 67
E EB
Figure 36 – Circuit diagram . 69
Figure 37 – Switching times . 70
Figure 38 – Circuit for the measurement of the transition frequency . 71
Figure 39 – Circuit for the measurement of complex common-emitter y parameters . 73
Figure 40 – Three-pole circuit for the measurement of y . 74
11e
Figure 41 – Three-pole circuit for the measurement of y . 74
22e
Figure 42 – Three-pole circuit for the measurement of y . 75
21e
Figure 43 – Three-pole circuit for the measurement of y . 76
12e
Figure 44 – Block diagram of the circuit for the measurement of s and s

11 22
parameters . 77

60747-7 Ó IEC:2010 – 5 –
Figure 45 – Block diagram of the circuit for the measurement of s and s

12 21
parameters . 79
Figure 46 – Basic block diagram for the measurement of the noise figure . 81
Figure 47 – Basic circuit for the measurement of the noise figure up to 3 MHz . 83
Figure 48 – Basic circuit for the measurement of the noise figure from 3 MHz to
300 MHz . 84
Figure 49 – Basic circuit for the measurement of the noise figure below 1 kHz (signal
generator method) . 86
Figure 50 – Basic circuit for the measurement of h /h . 88
21E1 21E2
Figure 51 – Matching of the collector current . 90
Figure 52 – Circuit diagram for measuring the on-state input voltage V , and off-
I(on)
state input voltage V . 90
I(off)
Figure 53 – Circuit diagram for measuring the bias resistor r . 91
Figure 54 – Circuit diagram and measuring the bias resistor r . 92
Figure 55 – Circuit diagram for measuring the on-state output voltage V . 93
O(on)
Figure 56 – Circuit diagram for measuring the off-sate output current I . 94
O(off)
Figure 57 – Test circuit for high temperature blocking . 96
Figure 58 – Circuit for Intermittent operating life . 97
Figure 59 – Expected number of cycles versus temperature rise DT . 97
vj
Figure A.1 – Typical DV versus collector-base (V ) characteristics . 99
EB CB
Figure A.2 – Typical safe operating area . 100

Table 1 – Acceptance defining characteristics and acceptance criteria . 35
Table 2 – Acceptance defining characteristics suitable for resistor biased transistor . 35
Table 3 – Acceptance defining characteristics after endurance tests for bipolar
transistors . 95
Table 4 – Minimum items of type and routine tests for transistors when applicable . 98

– 6 – 60747-7 Ó IEC:2010
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES –
DISCRETE DEVICES –
Part 7: Bipolar transistors
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60747-7 has been prepared by subcommittee 47E: Discrete
semiconductor devices, of IEC technical committee 47: Semiconductor devices.
This third edition cancels and replaces the second edition published in 2000 and
IEC 60747-7-5 published in 2005.
The main changes with respect to previous edition are listed below.
a) Clause 1 was amended by adding an item that should be included.
b) Clauses 3, 4, 5, 6 and 7 were amended by adding terms, definitions, suitable additions
and deletions those should be included.
c) The text of the second edition was combined with that of IEC 60747-7-5.
This standard is to be read in conjunction with IEC 60747-1:2006.

60747-7 Ó IEC:2010 – 7 –
The text of this standard is based on the following documents:
FDIS Report on voting
47E/404/FDIS 47E/408/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all the parts in the IEC 60747 series, under the general title Semiconductor devices –
Discrete devices, can be found on the IEC website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
 reconfirmed,
 withdrawn,
 replaced by a revised edition, or
 amended.
– 8 – 60747-7 Ó IEC:2010
SEMICONDUCTOR DEVICES –
DISCRETE DEVICES –
Part 7: Bipolar transistors
1 Scope
This part of IEC 60747-7 gives the requirements applicable to the following sub-categories of
bipolar transistors excluding microwave transistors.
– Small signal transistors (excluding switching and microwave applications);
– Linear power transistors (excluding switching, high-frequency, and microwave
applications);
– High-frequency power transistors for amplifier and oscillator applications;
– Switching transistors for high speed switching and power switching applications;
– Resistor biased transistors.
2 Normative references
The following referenced documents are indispensable for the application 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 60050-521:2002, International Electrotechnical Vocabulary – Part 521: Semiconductor
devices and integrated circuits
IEC 60747-1:2006, Semiconductor devices – Part 1: General
IEC 60747-4:2007, Semiconductor devices – Discrete devices – Part 4: Microwave diodes and
transistors
3 Terms and definitions
For the purposes of this document the following terms and definitions apply.
3.1 Specific functional regions
3.1.1
functional collector region
collection region that acquires principal-current charge carriers from the functional base
region through the (collecting) junction between it and the functional base region
NOTE In the normal operating mode, this functional region is located in the collector region and, in the inverse
operating mode, in the emitter region.
3.1.2
functional emitter region
supply region that delivers principal-current charge carriers into the functional base region
through the (emitting) junction between it and the functional base region.
NOTE In the normal operating mode, this functional region is located in the emitter region and, in the inverse
operating mode, in the collector region.

60747-7 Ó IEC:2010 – 9 –
3.1.3
functional base region
control region through which the principal current passes and in which the concentration of
principal-current charge carriers is the result of an applied base current
3.1.4
collector(-base) space-charge region;
collector(-base) depletion layer
space-charge region between the functional collector region and the functional base region
3.1.5
emitter(-base) space-charge region;
emitter(-base) depletion layer
space-charge region between the functional emitter region and the functional base region
3.2 Resistor biased transistor
3.2.1
general description
bipolar junction transistors that incorporate with two bias resistors. One bias resistor is
connected between the In terminal and the base region and the another between the base
region and the common terminal. The resistor biased transistor is specified as a logic circuit
element.
The graphical symbol as shown in Figure 1 is used in this standard for resistor biased
transistors npn or pnp.
Out (Collector)
r
In
r
Common (Emitter)
IEC  2910/10
Figure 1 – Resistor biased transistor graphical symbol
3.2.2
input terminal
terminal connected to the bias resistor 1
3.2.3
output terminal
terminal connected to a collector
3.2.4
common terminal
terminal connected to an emitter
3.2.5
bias resistor 1
resistor connected between the input terminal and the internal base of the transistor

– 10 – 60747-7 Ó IEC:2010
3.2.6
bias resistor 2
resistor connected between the internal base of the transistor and the common terminal
3.3 Terms related to ratings and characteristics
3.3.1
punch-through voltage
value of the collector-base voltage above which the open-circuit emitter-base voltage
increases almost linearly with increasing collector-base voltage
NOTE 1 At this voltage, the collector depletion layer extends through the base to the emitter depletion layer.
NOTE 2 "Reach-through voltage" is a term also in the USA.
3.3.2
saturation voltages
3.3.2.1
collector-emitter saturation voltage
voltage between the collector and emitter electrodes under conditions of base current beyond
which the collector current remains essentially constant as the base current increased.
NOTE This is the voltage between the collector and emitter electrodes when both the base-emitter and base-
collector junctions are forward biased.
3.3.2.2
base-emitter saturation voltage
voltage between the base and emitter electrodes under conditions of emitter current or
collector current and base current beyond which the collector current remains essentially
constant as the base current increased.
NOTE This is the voltage between the base and emitter electrodes when both the base-emitter and base-collector
junctions are forward biased.
3.3.3
cut-off current
reverse current
reverse current of the base-collector junction or base-emitter junction.
3.3.4
saturation resistance
resistance between collector and emitter terminals under specified conditions of base current
and collector current when the collector current is limited by the external circuit
NOTE The saturation resistance may be determined either as the ratio of total voltage to total current or as the
ratio of differential voltage to differential current; the method of determination should be specified.
3.3.5
emitter depletion layer capacitance
part of the capacitance across an emitter-base junction that is associated with its depletion
layer
NOTE The emitter depletion layer capacitance is a function of the total potential difference across the depletion
layer.
3.3.6
collector depletion layer capacitance
part of the capacitance across a collector-base junction that is associated with its depletion
layer
NOTE The depletion layer capacitance is a function of the total potential difference across the depletion layer.

60747-7 Ó IEC:2010 – 11 –
3.3.7
switching times
for bipolar transistors, the input waveform is the base current and the output waveform is the
collector current. The lower and upper limits are usually 10% and 90% of the amplitude.
3.3.7.1
turn on delay time
rise time
carrier storage time
fall time
t , t , t and t
d(on) r s f
see IEC 60050-521:2002,521-05-21, IEC 60050-521:2002,521-05-22, IEC 60050-521:2002,
521-05-23, IEC 60050-521:2002,521-05-24.
3.3.7.2
turn-on time
time interval between a step function change of the input signal level and the instant at which
the magnitude of the signal at the output terminals reaches a specified upper limit when the
semiconductor device is being switched from its non-conducting to its conducting state. The
lower and upper limits are usually 10 % and 90 % of the amplitude.
3.3.7.3
turn-off time
time interval between a step function change of the input signal level and the instant at which
the magnitude of the signal at the output terminals reaches a specified lower limit when the
semiconductor device is being switched from its conducting to its non-conducting state. The
lower and upper limits are usually 10 % and 90 % of the amplitude.
3.3.8
collector-emitter sustaining voltage
V
CE (SUS)
collector-emitter breakdown voltage at higher values of collector current where the breakdown
voltage is relatively constant over decreasing collector current for a specified termination
between base and emitter terminals
3.3.9
turn-on energy (per pulse)
E
on
energy dissipated in transistor during turn-on
3.3.10
turn-off energy (per pulse)
E
off
energy dissipated in transistor during turn-off
3.3.11
maximum frequency of oscillation
maximum frequency at which a transistor can be made to oscillate under specified conditions
NOTE This frequency approximates to the transition frequency.
3.3.12
transition frequency
f
T
frequency at which the modulus of the common-emitter small-signal short-circuit forward
current transfer ratio |h | has decreased to unity
21e
– 12 – 60747-7 Ó IEC:2010
3.3.13
transfer ratio
3.3.13.1
small-signal short-circuit forward current transfer ratio
ratio between the alternating output current and the small sinusoidal input current producing it
under small-signal conditions, the output being short-circuited to a.c.
3.3.13.2
static value of the forward current transfer ratio
ratio between the continuous (direct) output and the continuous (direct) input current, the
output voltage being held constant
3.3.13.3
inherent (large-signal) forward current transfer ratio
difference between the continuous (direct) collector current and the collector-base cut-off
current divided by the sum of the continuous (direct) base current and the collector-base cut-
off current at a specified constant value of the collector-emitter voltage
3.3.13.4
small-signal open-circuit reverse voltage transfer ratio
ratio of the alternating voltage appearing at the input terminals, when they are a.c. open-
circuited, to the alternating voltage applied to the output terminals, under small-signal
conditions
3.3.13.5
transient current ratio in saturation (of a switching transistor)
quotient of the collector current suddenly demanded from a transistor and the minimum base
current necessary to hold it in saturation
3.3.14
resistor ratio (of resistor biased transistor)
ratio of the values of bias resistor 2 and bias resistor 1
3.3.15
input voltage (of resistor biased transistor)
voltage between the input terminal and the common terminal of the device
3.3.16
off-state input voltage (of resistor biased transistor)
input voltage at which the output current has reached its defined off-state value
3.3.17
on-state input voltage (of resistor biased transistor)
input voltage at which the output current has reached its defined on-state value
3.3.18
output voltage (of resistor biased transistor)
voltage between the output terminal and the common terminal of the device
3.3.19
off-state output current (of resistor biased transistor)
current flowing into the output terminal in the off-state
3.3.20
on-state output voltage (of resistor biased transistor)
current flowing into the output terminal in the off-state output voltage with specified I and I in
i o
such a way that the transistor is in its specified on state

60747-7 Ó IEC:2010 – 13 –
4 Letter symbols
4.1 General
Mostly, existing letter symbols are added to the terms in titles. When several distinct forms
exist, the most commonly used form is given.
Subclause 4.2 of IEC 60747-1:2006 applies.
4.2 Additional subscripts
In addition to the list of recommended general subscripts given in Clause 4 of IEC 60747-
1:2006, the following subscripts are recommended for bipolar transistors:
B,b = base
C,c = collector
E,e = emitter
fl = floating
pt = punch-through (penetration, reach-through)
R,r (not as a first subscript) = specified resistance
sat = saturation
X = specified circuit
s = storage
T = transition
4.3 Lists of letter symbols
4.3.1 General
The symbols contained in the following lists are recommended for use in the field of bipolar
transistors. They have been compiled in accordance with the general rules in Clause 4 of
IEC 60747-1:2006.
– 14 – 60747-7 Ó IEC:2010
4.3.2 Voltages
Name and designation Letter symbol Remarks
Collector-base (d.c.) voltage V
CB
Collector-emitter (d.c.) voltage V
CE
Emitter-base (d.c.) voltage V
EB
Base-emitter (d.c.) voltage V
BE
Collector-base (d.c.) voltage
V
CBO
with I = 0 I specified
E C
Emitter-base (d.c.) voltage
V
EBO
with I = 0 I specified
C E
Collector-emitter (d.c.) voltage
V
CEO
with I = 0 I specified
B C
Collector-emitter (d.c.) voltage
V
CER
with R = R I specified
BE C
Collector-emitter (d.c.) voltage
V
CES
with V = 0 I specified
BE C
Collector-emitter (d.c.) voltage
with V = X specified
BE
V
CEX
(reverse biased emitter-base
junction) I specified
C
Floating voltage, emitter-base
V
EBfl
with I = 0 V specified
E CB
Punch-through (penetration) voltage V
pt
Saturation voltage, collector-emitter
V
CEsat
with I specified I specified
B C
Saturation voltage, base-emitter
V
BEsat
with I specified I specified
B C
60747-7 Ó IEC:2010 – 15 –
4.3.3 Currents
Name and designation Letter symbol Remarks
I
Base (d.c.) current
B
Collector (d.c.) current I
C
Emitter (d.c.) current I
E
Collector cut-off current
I
CBO
with I = 0 V specified
E CB
Collector cut-off current
I
CEO
with I = 0 V specified
B CE
Emitter cut-off current
I
EBO
with I = 0 V specified
C EB
Collector cut-off current
I
CER
with R = R V specified
BE CE
Collector cut-off current
I
CES
with V = 0 V specified
BE CE
Collector cut-off current
I
CEX
with V = X V specified
BE CE
Base cut-off current
I
BEX
with V = X V specified
BE BE
4.3.4 Powers
Name and designation Letter symbol Remarks
Collector power dissipation
P
C
with T or T specified
a c
Total input power (d.c. or average)
to all electrodes P
tot
with T or T specified
a c
4.3.5 Electrical parameters
4.3.5.1 Static parameters (specified for bias conditions)
Name and designation Letter symbol Remarks
I I
Static value of the forward current transfer ratio C E
h = = -1 with V = constant
h or h 21E CE
21E FE
(in common-emitter configuration)
I I
B B
V
BE
Static value of the input resistance
h = with V = constant
h or h
11E CE
11E IE
(in common-emitter configuration)
I
B
– 16 – 60747-7 Ó IEC:2010
4.3.5.2 Small-signal parameters (specified for bias and frequency conditions)
Name and designation Letter symbol Remarks
Small signal value of the short-circuit

input impedance:
V
be
h = with V = constant
– in common-emitter configuration h or h
11e ce
11e ie
I
b
V
eb
h = with V = constant
– in common-base configuration h or h cb
11b
11b ib
I
e
Small-signal value of the open-circuit

reverse voltage transfer ratio:
V
be
h = with I = constant
h or h
– in common-emitter configuration 12 e b
12e re
V
ce
V
eb
h = with I = constant
– in common-base configuration h or h 12b e
12b rb
V
cb
Small-signal value of the short-circuit

forward current transfer ratio:
I
c
h = with V = constant
h or h
– in common-emitter configuration 21e ce
21e fe
I
b
I
c
h = with V = constant
h or h
– in common-base configuration 21b cb
21b fb
I
e
Small-signal value of the open-circuit

output admittance:
I
c
h = with I = constant
– in common-emitter configuration h or h
22 e b
22e oe
V
ce
I
c
h = with I = constant
– in common-base configuration h or h
22b e
22b ob
V
cb
Real part of the small-signal value
h = Re(h )+ Im(h )
11e 11e 11e
of the short-circuit input impedance:
h = Re(h )+ Im( h )
11b 11b 11b
– in common-emitter configuration Re(h )
11e
Re(h )
– in common-base configuration
11b
Imaginary part of the small-signal value

of the short-circuit input impedance:
– in common-emitter configuration Im(h )
11e
– in common-base configuration Im(h )
11b
Input capacitance, output short-circuited

to a.c.:
h @ Re(h )+
– in common-emitter configuration C or C
11e 11e
11es ies
jwC
11es
h @ Re(h )+
– in common-base configuration C or C
11b 11b
11bs ibs
jwC
11bs
Input capacitance, output open-circuited to a.c.:
– in common-emitter configuration C or C
11eo ieo
– in common-base configuration C or C
11bo ibo
60747-7 Ó IEC:2010 – 17 –
4.3.5.2 (continued)
Name and designation Letter symbol Remarks
Output capacit
...