IEC 60440:2012

Method of measurement of non-linearity in resistors

IEC 60440:2012 specifies a method of measurement and associated test conditions to assess the magnitude of non-linear distortion generated in a resistor. This method is applied if prescribed by a relevant component specification, or if agreed between a customer and a manufacturer. This International Standard cancels and replaces the Technical Report IEC/TR 60440, published in 1973. The major changes with regard to the Technical Report are:
- change of the principle parameter's term from "third harmonic attenuation" to "third harmonic ratio";
- addition of advice on the prescription of requirements in a relevant component specification;
- addition of a set of recommended measuring conditions for a specimen with a rated dissipation of less than 100 mW;
- a complete editorial revision.

Méthode de mesure de la non-linéarite des résistances

La CEI 60440:2012 spécifie une méthode de mesure et les conditions d'essais associées pour déterminer l'amplitude de la distorsion non linéaire générée dans une résistance. Cette méthode est appliquée si elle est prescrite par une spécification applicable au composant, ou si elle fait l'objet d'un accord entre un client et un fabricant. La présente Norme internationale annule et remplace le Rapport technique CEI/TR 60440, paru en 1973. Les modifications principales par rapport au Rapport technique sont les suivantes:
- modification du terme du paramètre principal d'"affaiblissement de troisième harmonique" en "rapport de troisième harmonique";
- ajout de conseils sur la prescription d'exigences dans une spécification applicable au composant;
- ajout d'un ensemble de conditions de mesure recommandées pour un spécimen ayant une dissipation assignée inférieure à 100 mW;
- révision éditoriale complète.

General Information

• Status: Published
• Publication Date: 12-Jul-2012
• ICS: 31.040.01 - Resistors in general
• Technical Committee: TC 40 - Capacitors and resistors for electronic equipment
• Current Stage: PPUB - Publication issued
• Start Date: 13-Jul-2012
• Completion Date: 15-Aug-2012

Relations

• Replaces: IEC TR 60440:1973 - Method of measurement of non-linearity in resistors
• Effective Date: 05-Sep-2023

IEC 60440:2012 Overview

IEC 60440:2012 is an international standard published by the International Electrotechnical Commission (IEC) that defines the method of measurement of non-linearity in resistors. This standard establishes a precise procedure and test conditions to assess the magnitude of non-linear distortion generated by resistors. It replaces the earlier IEC/TR 60440 Technical Report from 1973, incorporating important updates to terminology, measurement techniques, and recommended conditions, particularly for resistors with rated dissipation less than 100 mW.

Non-linearity testing plays a vital role in ensuring the integrity and reliability of resistors by detecting potential defects such as inhomogeneous film spots, residual film in spiraling grooves, or contact instabilities between leads and resistive elements. This method is widely used either when specified by a component specification or agreed upon by manufacturers and customers.

Key Topics

• Measurement Principle: IEC 60440 defines a method where a pure sinusoidal current is applied to the resistor. Any non-linearity causes voltage distortion and generates harmonic frequencies-primarily the third harmonic. Measuring the third harmonic voltage relative to the fundamental frequency voltage helps quantify non-linearity.

• Third Harmonic Ratio: A key metric replacing the older "third harmonic attenuation" term. The third harmonic ratio (expressed in decibels) is the ratio between the fundamental voltage and the electromotive force (e.m.f.) of the third harmonic. It provides a clearer representation of distortion caused by resistor non-linearity.

• Measurement System Requirements:

  • Fundamental and harmonic filtering to isolate third harmonic signals.
  • High impedance at the fundamental frequency for the filter.
  • High impedance from the signal generator at the third harmonic frequency to avoid loading distortion signals.
  • Power amplifiers, voltmeters, and filters calibrated to minimize added noise and distortion.

• Test Conditions: The standard includes detailed advice on environmental conditions, specimen preparation, measurement procedures, and precautions to ensure reproducibility and accuracy.

• Correction Factors: The standard discusses necessary corrective terms to adjust measured voltages to true e.m.f. values of the third harmonic. It provides graphical and tabular data to assist in these corrections.

• Updated Terminology and Recommendations: Key updates include refining terminology from "third harmonic attenuation" to "third harmonic ratio," added advice for inclusion in component specifications, and recommended measurement conditions for low power resistors (rated dissipation below 100 mW).

Applications

IEC 60440:2012 is crucial for manufacturers, quality control engineers, and designers working with passive electronic components, particularly resistors. The standard’s practical applications include:

• Quality Assurance: Identifying potential infant mortality and reliability issues by detecting non-linear distortions indicating manufacturing defects.

• Component Specification: Guiding engineers in creating robust component specifications that include reliable, standardized non-linearity requirements.

• Inline Production Testing: Offering a rapid, cost-effective in-line screening method to reject defective resistors early in production, improving overall product yield and reliability.

• Research and Development: Supporting the development of resistive components with superior linearity by providing a benchmark measurement method.

• Compliance Verification: Ensuring components meet specified non-linearity levels for specialized applications such as precision electronics, sensors, and instrumentation.

Related Standards

• IEC 60068-1: Environmental testing standards referenced in IEC 60440 to ensure environmental conditions during testing are properly controlled.

• Other IEC standards for capacitors and resistors produced by IEC technical committee 40, which address related characteristics and testing methods enhancing component reliability and performance validation.

• ISO/IEC Directives, Part 2: Govern the drafting and structure of IEC standards, including IEC 60440.

Summary

IEC 60440:2012 provides a standardized, internationally recognized methodology to measure and evaluate the non-linearity of resistors by focusing on the third harmonic voltage distortion under sinusoidal excitation. This enables consistent assessment of resistor quality, helping manufacturers and users detect faults early while maintaining high standards for resistive components in electrical and electronic systems. With updated terminology, test conditions, and measurement techniques, IEC 60440:2012 remains essential for quality assurance, inline testing, and specification of resistor non-linearity in modern electronics manufacturing.

Standards Content (Sample)

IEC 60440 ®
Edition 1.0 2012-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Method of measurement of non-linearity in resistors

Méthode de mesure de la non-linéarite des résistances

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IEC 60440 ®
Edition 1.0 2012-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Method of measurement of non-linearity in resistors

Méthode de mesure de la non-linéarite des résistances

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX Q
ICS 31.040 ISBN 978-2-83220-228-9

– 2 – 60440 © IEC:2012
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Method of measurement . 6
4.1 Measurement principle . 6
4.2 Measuring circuit . 8
4.3 Measurement system requirements . 9
4.3.1 Measuring frequency . 9
4.3.2 Noise level of the measuring system . 9
4.3.3 Third harmonic ratio of the measuring system . 9
4.3.4 Power amplifier . 9
4.3.5 Voltmeter . 10
4.3.6 Filter . 10
4.3.7 Test fixture . 10
4.4 Verification of the measuring system . 10
5 Measurement procedure . 10
5.1 Environmental conditions . 10
5.2 Preparation of specimen . 10
5.3 Measurement conditions . 10
5.4 Procedure . 11
5.5 Precautions . 11
6 Evaluation of measurement results . 11
6.1 Evaluation . 11
6.2 Requirements . 12
7 Information to be given in the relevant component specification. 12
Annex A (informative) Reference to IEC/TR 60440 . 15
Bibliography . 16

Figure 1 – Equivalent circuit at the fundamental frequency . 6
Figure 2 – Equivalent circuit at the third harmonic frequency . 7
Figure 3 – Corrective term Δ . 8
Figure 4 – Block schematic of a suitable measuring system . 9

Table 1 – Recommended measuring conditions (1 of 2) . 13

60440 © IEC:2012 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
METHOD OF MEASUREMENT OF NON-LINEARITY IN RESISTORS

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
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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 60440 has been prepared by committee 40: Capacitors and
resistors for electronic equipment.
This International Standard cancels and replaces the Technical Report IEC/TR 60440,
published in 1973.
The major changes with regard to the Technical Report are:
– change of the principle parameter’s term from “third harmonic attenuation” to “third
harmonic ratio”;
– addition of advice on the prescription of requirements in a relevant component
specification;
– addition of a set of recommended measuring conditions for a specimen with a rated
dissipation of less than 100 mW;
– a complete editorial revision.

– 4 – 60440 © IEC:2012
The text of this standard is based on the following documents:
FDIS Report on voting
40/2155/FDIS 40/2167/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.
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.
60440 © IEC:2012 – 5 –
METHOD OF MEASUREMENT OF NON-LINEARITY IN RESISTORS

1 Scope
Non-linearity testing is a method to evaluate the integrity of a resistive element. It may be
applied as an effective inline screening method suitable to detect and eliminate potential
infant mortality failures in passive components. The method is fairly rapid, convenient, and the
associated equipment is relatively inexpensive.
Typical effects causing non-linearity on resistors are e.g. inhomogeneous spots within a
resistive film, traces of film left in the spiraling grooves, or contact instability between a
connecting lead or termination and the resistive element.
This International Standard specifies a method of measurement and associated test
conditions to assess the magnitude of non-linear distortion generated in a resistor. This
method is applied if prescribed by a relevant component specification, or if agreed between a
customer and a manufacturer.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60068-1, Environmental testing – Part 1: General and guidance
3 Terms and definitions
For the puposes of this document the following terms and definitions apply.
3.1
electromotive force
e.m.f.
difference in potential that tends to give rise to an electric current
3.2
non-linearity
deviation of a component’s impedance from Ohm’s law, resulting in voltage of harmonic
frequencies when subjected to sinusoidal current
3.3
third harmonic ratio
A
ratio of the fundamental voltage over the e.m.f. of the third harmonic
Note 1 to entry: The third harmonic ratio is expressed in dB.
Note 2 to entry: The third harmonic ratio has been addressed before as third harmonic attenuation. This historic
convention is misleading as it wrongly suggests harmonic frequencies originating from the test equipment being
attenuated or filtered by the components under test. The misleading term should therefore be avoided.

– 6 – 60440 © IEC:2012
4 Method of measurement
4.1 Measurement principle
A pure sinusoidal current is passed through the component under test. If the impedance of the
component is not perfectly linear, the voltage across the component will be distorted and
contain harmonics. One or more of these harmonics can be measured and the magnitude of
these distortions is a measure of the non-linearity in the component. It is recommended to
measure the third harmonic, as it is the dominant one.
The third harmonic voltage appearing across a component needs to be separated from the
fundamental voltage and from any other harmonic voltage for the measurement. This is
accomplished by a filter circuit letting the harmonic voltage pass through while featuring very
high impedance at the fundamental frequency. Also, the generator of the fundamental
frequency needs to feature very high impedance at the third harmonic frequency so as not to
act as a load to the generated distortions.
Hence, the equivalent circuit of the generator part operating at the fundamental frequency is
quite simple, as shown in Figure 1.

I
U R
T
IEC  1432/12
Key
I Sinusoidal current
U Fundamental voltage across the resistor under test
R Impedance of the resistor under test at the fundamental frequency
T
Figure 1 – Equivalent circuit at the fundamental frequency
The equivalent circuit for the third harmonic frequency is built around the test specimen
represented by a linear impedance with a zero-impedance harmonic generator in series. This
signal source loads the measuring system represented by its impedance as seen from the test
terminals, see Figure 2.
60440 © IEC:2012 – 7 –
R
T3
U
R
3 3
E
IEC  1433/12
Key
E e.m.f. of the third harmonic
R Impedance of the resistor under test at the third harmonic frequency
T3
R Impedance of the measuring circuit at the third harmonic frequency, seen from the test terminals
U Third harmonic voltage
Figure 2 – Equivalent circuit at the third harmonic frequency
In this circuit the e.m.f. of the third harmonic E is divided into the measurable third harmonic
voltage U
R
U = ⋅E (1)
3 3
R + R
3 T3
Hence, the e.m.f. of the third harmonic E in the component can be determined by
 
R
T3
 
E = 1+ ⋅U (2)
3 3
 
R
 3 
The corrective term ∆ for the reduction of U to the origin E is
3 3
 
R
T3
Δ = 20 ⋅log 1+  (3)
 
R
 3 
In many cases it can be shown for a range of resistors under test that the impedance R at
T3
the third harmonic frequency is equal or very close to the impedance R at the fundamental
T
frequency. Then the corrective term ∆ in decibels is
 R 
T
 
Δ = 20 ⋅log 1+ (4)
 
R
 
NOTE 1 For fixed film resistors this equality of R and R can generally be assumed with sufficient accuracy.
T3 T
Numeric values for the corrective term ∆ can be obtained from Figure 3 or for specific sets of
impedance R and specimen resistance R from Table 1.
3 T
– 8 – 60440 © IEC:2012
0,1 1 10 100
R /R
T 3
IEC  1434/12
Figure 3 – Corrective term Δ
A suitable range for the fundamental frequency f for measurements on resistors is between
10 kHz and 40 kHz. This frequency range enables the test circuit to be set up without too
much difficulty.
NOTE 2 Another method is using a bridge which is balanced at the fundamental frequency, where the harmonics
appear across the bridge diagonal. This method requires individual balancing of the bridge for each specimen,
which may be suitable for occasional use in a laboratory environment.
4.2 Measuring circuit
Figure 4 shows a block schematic of a suitable measuring circuit.
A distortion-free impedance matching device may be used to switch R in order to achieve
good matching to the test specimen R . Examples of suitable values of R are 10 Ω; 100 Ω;
T 3
1 kΩ; 10 kΩ and 100 kΩ; these values are used for specifying the test conditions in Table 1.
The suitability of the measuring circuit for measurements on resistors with resistance values
covering a wide range depends on the lowest and highest available impedance R of the
circuit. The range of values for R proposed above grants suitability for measurements on
specimen R with their resistance being in the range of 1 Ω to at least 10 MΩ.
T
However, there is an overriding influence of the correcting term ∆ depending on the ratio of
resistance under test R over impedance R , see Table 1 and Figure 3.
T 3
∆  (dB)
60440 © IEC:2012 – 9 –
S
U U
G V
1 V 3
VA A LP BP
R
R
T
IEC  1435/12
Key
G Oscillator, at the fundamental frequency f
S Switch for applying the test signal to the test specimen
VA Variable attenuator
A Power amplifier
LP Low-pass filter
U r.m.s. voltage at the fundamental frequency f
1 1
BP Band-pass filter
U r.m.s. voltage at the third harmonic frequency f
3 3
R Resistor under test
T
R Impedance of the measuring circuit at the third harmonic frequency f , seen from the test terminals.
3 3
Figure 4 – Block schematic of a suitable measuring system
4.3 Measurement system requirements
4.3.1 Measuring frequency
The fundamental frequency f shall be 10 kHz and thus the third harmonic frequency f shall
1 3
be 30 kHz, unless otherwise specified in the relevant component specification.
4.3.2 Noise level of the measuring system
The noise level referred to the test terminals shall not be higher than 0,2 µV at R = 1 kΩ.
4.3.3 Third harmonic ratio of the measuring system
The third harmonic ratio 20 ⋅ log (U E ) shall be higher than 140 dB for most of the
10 1 3
impedance range when the required dissipation P is applied to a virtually linear component.
The required dissipation is 0,25 VA, as given in Table 1, or a value prescribed by the relevant
component specification, e.g with reference to the rated dissipation.
4.3.4 Power amplifier
The power amplifier shall be capable of delivering an apparent power of four times the
required dissipation into a resistive component under test, in order to ensure sufficient
linearity.
Hence, the power amplifier shall be capable of delivering an apparent power of 1 VA if the
required dissipation is 0,25 VA as given in Table 1.

– 10 – 60440 © IEC:2012
4.3.5 Voltmeter
The error of the voltmeter for measurement of the voltage U at the fundamental frequency
shall be less than 5 % of its full scale deflection.
The error of the voltmeter for measurement of the voltage U at the third harmonic frequency
shall be less than 10 % of its full scale deflection.
4.3.6 Filter
The cut-off frequency of the low-pass filter shall be immediately above the fundamental
freuqency f .
The band-pass filter shall permit the third-harmonic frequency f to pass through, while it shall
provide very high attenuation at the fundamental frequency f .
Precautions shall be taken to avoid non-linear distortion from the components near the test
specimen in the low-pass and band-pass filters. The filter inductors for instance shall not
contain cores of magnetic material.
4.3.7 Test fixture
The test fixture for the specimen R shall be capable of providing safe electrical connection.
T
4.4 Verification of the measuring system
Reference resistors with known non-linearity shall be used to verify the integrity of the
measuring system.
5 Measurement procedure
5.1 Environmental conditions
Unless otherwise specified, all tests shall be carried out under standard atmospheric
conditions for measurement and tests as specified in IEC 60068-1.
5.2 Preparation of specimen
The specimen shall be kept for at least 2 h in the environmental conditions prescribed in 5.1.
5.3 Measurement conditions
The choice of system impedances R is determined by the properties of the actual
measurement system. Table 1 is based on examples of suitable values for R .
The fundamental test voltage U shall be chosen from Table 1, unless otherwise specified in
the relevant component specification, e.g. relative to the rated dissipation.
Analysis shows that the third harmonic ratio depends significantly on the choice of the
fundamental voltage as the readings of the third harmonic voltage U show an exponential
relationship over the ratio of applied fundamental voltages. Comparison of the non-linearity of
different products should therefore always be based on identical prescriptions for dissipation
and voltage limitation in order to define an identical fundamental voltage for each resistance
value.
The application of the fundamental voltage results in a dissipation, and thus in a temperature
rise within the specimen. Depending on its temperature coefficient of resistance (TCR), the

60440 © IEC:2012 – 11 –
specimen resistance will change, which will change the actual applied fundamental voltage.
Depending on the respective temperature rise and TCR, this effect may be insignificant or not.
Limiting the duration of the application of the fundamental voltage may be a suitable way out
of this problem, if set below the thermal time constant of the specimen.
The relevant component specification shall state respective requirements, if applicable.
5.4 Procedure
The specimen shall be inserted into the test fixture and properly connected to the test
terminals.
The system impedance R shall be selected in order to achieve the best possible impedance
matching.
The fundamental voltage shall be applied, e.g. by closing the switch S in a system according
to Figure 4, and adjusted to the prescribed value.
The third harmonic voltage U shall be read.
The application of the fundamental voltage shall not exceed the prescribed duration, if
applicable.
5.5 Precautions
Ferromagnetic materials give rise to harmonic distortion and care shall be taken to avoid
influence from e.g. iron in the immediate vicinity of the component which can mask component
non-linearities especially at high currents.
6 Evaluation of measurement results
6.1 Evaluation
The reading of the third harmonic voltage U shall be used to calculate the third harmonic
ratio.
The third harmonic ratio A in decibels is
U
A = 20 ⋅ log
3 10
E
U E
1 3
= 20 ⋅ log − 20 ⋅ log (5)
10 10
U U
ref ref
U U  R 
1 3 T3
 
= 20 ⋅ log − 20 ⋅ log − 20 ⋅ log 1+
10 10 10
 
U U R
ref ref 3
 
where
U is the fundamental voltage across the resistor under test
U is the basis for voltage ratios, arbitrarily set
ref
E is the e.m.f. of the third harmonic in the component
U is the measured third harmonic voltage
R is the impedance of the resistor under test at the third harmonic frequency
T3
R is the impedance of the measuring circuit at the third harmonic frequency, seen from the
test terminals (source impedance)

– 12 – 60440 © IEC:2012
In Equation (5), the logarithmic term describing the fundamental voltage may be abbreviated
as D with
U
D = 20 ⋅ log (6)
U
ref
NOTE The calculation of the third harmonic ratio requires a common U for all used logarithms of voltage ratios;
ref
throughout this standard, U = 1 V is used for the 0 dB reference level.
ref
The abbreviation of a logarithmic expression 20·log (U/U ) to 20·log U is mathematically incorrect and
10 ref
particularly bears the risk of confusion when the used reference voltage is no longer considered. Hence the
abbreviated form is not an appropriate expression.
With the above definitions of D in Equation (6) and of ∆ in 4.1, Equation (5) can be simplified
to
U
A =D −20 ⋅log −Δ (7)
3 10
U
ref
6.2 Requirements
Acceptance criteria for non-linearity of tested products shall be given with reference to a
required minimum third harmonic ratio A in the relevant component specification.
Such acceptance criteria should be stated through a fixed minimum value, typically given as a
function of the specimen resistance.
Superior selectivity of non-linearity screening is achievable through the use of a dynamic
minimum value relative to the statistical distribution of non-linearity within an analyzed batch
in addition to a fixed minimum value. Such dynamic requirement should be referenced to a
batch’s mean value and a multiple of its standard deviation, e.g. like ≥ A − 3σ .
7 Information to be given in the relevant component specification
When this test is included in a relevant component specification, the following details shall be
given as far as they are applicable:
Subclause
a) the fundamental frequency
4.2
b) the environmental condition for this measurement
5.1
c) the dissipation to be provided through the fundamental voltage
5.3, Table 1
d) a limitation to the fundamental voltage, if applicable
5.3, Table 1
e) a limitation to the duration of application of the fundamental voltage,
if applicable
5.3
The relevant component specification shall specify for its own purpose:
Subclause
f) acceptance criteria to the third harmonic ratio A
6.2
60440 © IEC:2012 – 13 –
R , for the
Table 1 gives the values for the recommended impedance of the measuring circuit
corresponding corrective term ∆ and for the fundamental voltage U of the recommended
measuring conditions for specimen R with a resistance in the range of 1 Ω to 22 MΩ.
T
Table 1 – Recommended measuring conditions (1 of 2)
Specimen’s rated dissipation P
r
a
b
P ≥ 0,25 W 0,25 W > P ≥ 0,1 W 0,1 W > P
R R ∆
r r r
3 T
c d c d c d
Ω Ω dB
U D P U D P U D P
1 1 1
V dB mW V dB mW V dB mW
1,0 0,8 0,50 −6,0 250 0,32 −10,0 100 0,22 −13,0 50
1,2 1,0 0,55 −5,2 250 0,35 −9,2 100 0,24 −12,2 50
1,5 1,2 0,61 −4,3 250 0,39 −8,2 100 0,27 −11,2 50
1,8 1,4 0,67 −3,5 250 0,42 −7,4 100 0,30 −10,5 50
2,2 1,7 0,74 −2,6 250 0,47 −6,6 100 0,33 −9,6 50
2,7 2,1 0,82 −1,7 250 0,52 −5,7 100 0,37 −8,7 50
3,3 2,5 0,91 −0,8 250 0,57 −4,8 100 0,41 −7,8 50
3,9 2,9 0,99 −0,1 250 0,62 −4,1 100 0,44 −7,1 50
4,7 3,3 1,08 0,7 250 0,69 −3,3 100 0,48 −6,3 50
5,6 3,9 1,18 1,5 250 0,75 −2,5 100 0,53 −5,5 50
6,8 4,5 1,30 2,3 250 0,82 −1,7 100 0,58 −4,7 50
8,2 5,2 1,43 3,1 250 0,91 −0,9 100 0,64 −3,9 50
10 6,0 1,58 4,0 250 1,00 0,0 100 0,71 −3,0 50
12 6,8 1,73 4,8 250 1,10 0,8 100 0,77 −2,2 50
15 8,0 1,94 5,7 250 1,22 1,8 100 0,87 −1,2 50
18 8,9 2,12 6,5 250 1,34 2,6 100 0,95 −0,5 50
22 10,1 2,35 7,4 250 1,48 3,4 100 1,05 0,4 50
27 11,4 2,60 8,3 250 1,64 4,3 100 1,16 1,3 50
33 2,5 2,87 9,2 250 1,82 5,2 100 1,28 2,2 50
39 2,9 3,12 9,9 250 1,97 5,9 100 1,40 2,9 50
47 3,3 3,43 10,7 250 2,17 6,7 100 1,53 3,7 50
56 3,9 3,74 11,5 250 2,37 7,5 100 1,67 4,5 50
68 4,5 4,12 12,3 250 2,61 8,3 100 1,84 5,3 50
82 5,2 4,53 13,1 250 2,86 9,1 100 2,02 6,1 50
100 6,0 5,00 14,0 250 3,16 10,0 100 2,24 7,0 50
120 6,8 5,48 14,8 250 3,46 10,8 100 2,45 7,8 50
150 8,0 6,12 15,7 250 3,87 11,8 100 2,74 8,8 50
180 8,9 6,71 16,5 250 4,24 12,6 100 3,00 9,5 50
220 10,1 7,42 17,4 250 4,69 13,4 100 3,32 10,4 50
270 11,4 8,22 18,3 250 5,20 14,3 100 3,67 11,3 50
330 2,5 9,08 19,2 250 5,74 15,2 100 4,06 12,2 50
390 2,9 9,87 19,9 250 6,24 15,9 100 4,42 12,9 50
470 3,3 10,8 20,7 250 6,86 16,7 100 4,85 13,7 50
560 3,9 11,8 21,5 250 7,48 17,5 100 5,29 14,5 50
680 4,5 13,0 22,3 250 8,25 18,3 100 5,83 15,3 50
820 5,2 14,3 23,1 250 9,06 19,1 100 6,40 16,1 50
1 k
1,0 k 6,0 15,8 24,0 250 10,0 20,0 100 7,07 17,0 50
1,2 k 6,8 17,3 24,8 250 11,0 20,8 100 7,75 17,8 50
1,5 k 8,0 19,4 25,7 250 12,2 21,8 100 8,66 18,8 50
1,8 k 8,9 21,2 26,5 250 13,4 22,6 100 9,49 19,5 50
2,2 k 10,1 23,5 27,4 250 14,8 23,4 100 10,5 20,4 50
2,7 k 11,4 26,0 28,3 250 16,4 24,3 100 11,6 21,3 50
3,3 k 2,5 28,7 29,2 250 18,2 25,2 100 12,8 22,2 50
3,9 k 2,9 31,2 29,9 250 19,7 25,9 100 14,0 22,9 50
4,7 k 3,3 34,3 30,7 250 21,7 26,7 100 15,3 23,7 50
10 k
5,6 k 3,9 37,4 31,5 250 23,7 27,5 100 16,7 24,5 50
6,8 k 4,5 41,2 32,3 250 26,1 28,3 100 18,4 25,3 50
8,2 k 5,2 45,3 33,1 250 28,6 29,1 100 20,2 26,1 50

– 14 – 60440 © IEC:2012
Table 1 (2 of 2)
Specimen’s rated dissipation P
r
a
b
P ≥ 0,25 W 0,25 W > P ≥ 0,1 W 0,1 W > P
R R ∆
r r r
3 T
c d c d c d
dB
Ω Ω
U D P U D P U D P
1 1 1
V dB mW V dB mW V dB mW
10 k 6,0 50,0 34,0 250 31,6 30,0 100 22,4 27,0 50
12 k 6,8 54,8 34,8 250 34,6 30,8 100 24,5 27,8 50
15 k 8,0 61,2 35,7 250 38,7 31,8 100 27,4 28,8 50
10 k
18 k 8,9 67,1 36,5 250 42,4 32,6 100 30,0 29,5 50
22 k 10,1 74,2 37,4 250 46,9 33,4 100 33,2 30,4 50
27 k 11,4 82,2 38,3 250 52,0 34,3 100 36,7 31,3 50
33 k 2,5 90,8 39,2 250 57,4 35,2 100 40,6 32,2 50
39 k 2,9 98,7 39,9 250 62,4 35,9 100 44,2 32,9 50
47 k 3,3 108 40,7 250 68,6 36,7 100 48,5 33,7 50
56 k 3,9 118 41,5 250 74,8 37,5 100 52,9 34,5 50
68 k 4,5 130 42,3 250 82,5 38,3 100 58,3 35,3 50
82 k 5,2 143 43,1 250 90,6 39,1 100 64,0 36,1 50
100 k 6,0 158 44,0 250 100 40,0 100 70,7 37,0 50
120 k 6,8 173 44,8 250 110 40,8 100 77,5 37,8 50
150 k 8,0 194 45,7 250 122 41,8 100 86,6 38,8 50
180 k 8,9 212 46,5 250 134 42,6 100 94,9 39,5 50
220 k 10,1 235 47,4 250 148 43,4 100 105 40,4 50
270 k 11,4 260 48,3 250 164 44,3 100 116 41,3 50
330 k 12,7 287 49,2 250 182 45,2 100 128 42,2 50
390 k 13,8 312 49,9 250 197 45,9 100 140 42,9 50
470 k 15,1 343 50,7 250 217 46,7 100 153 43,7 50
560 k 16,4 374 51,5 250 237 47,5 100 167 44,5 50
680 k 17,8 412 52,3 250 261 48,3 100 184 45,3 50
100 k 820 k 19,3 453 53,1 250 286 49,1 100 202 46,1 50
1,0 M 20,8 500 54,0 250 316 50,0 100 224 47,0 50
1,2 M 22,3 548 54,8 250 346 50,8 100 245 47,8 50
1,5 M 24,1 612 55,7 250 387 51,8 100 274 48,8 50
1,8 M 25,6 671 56,5 250 424 52,6 100 300 49,5 50
2,2 M 27,2 742 57,4 250 469 53,4 100 332 50,4 50
2,7 M 28,9 822 58,3 250 520 54,3 100 367 51,3 50
3,3 M 30,6 908 59,2 250 574 55,2 100 406 52,2 50
3,9 M 32,0 987 59,9 250 624 55,9 100 442 52,9 50
4,7 M 33,6 1 084 60,7 250 686 56,7 100 485 53,7 50
5,6 M 35,1 1 183 61,5 250 748 57,5 100 529 54,5 50
6,8 M 36,8 1 304 62,3 250 825 58,3 100 583 55,3 50
8,2 M 38,4 1 432 63,1 250 906 59,1 100 640 56,1 50
10 M 40,1 1 581 64,0 250 1 000 60,0 100 707 57,0 50
12 M 41,7 1 732 64,8 250 1 095 60,8 100 775 57,8 50
15 M 43,6 1 936 65,7 250 1 225 61,8 100 866 58,8 50
18 M 45,2 2 121 66,5 250 1 342 62,6 100 949 59,5 50
22 M 46,9 2 345 67,4 250 1 483 63,4 100 1 049 60,4 50
a
The parameters for other values of R than those shown here shall be calculated using the resistance R ,
T T
the dissipation P and, if applicable, a limitation to the fundamental voltage U .
b
The given figures for the correction term ∆ only apply if the measuring circuit uses the source impedances
R shown here.
c
A limitation may apply to the voltage at fundamental frequency, thereby limiting the value D and the
actual dissipation P.
d
The decibel ratio D of the fundamental voltage is based upon U = 1 V for the 0 dB reference level.
ref
60440 © IEC:2012 – 15 –
Annex A
(informative)
Reference to IEC/TR 60440
The drafting of this standard has resulted in a new structure. The following table indicates the
new clause and subclause numbers with respect to the Technical Report, published in 1973.
a
IEC/TR 60440 IEC 60440:2012 Notes
st
1 edition
Clause/Subclause Clause/Subclause
1 Scope and object are merged into one
— 2 New clause
— 3 New clause
4.1 —
4.0
4.1
4.2 —
4.2
4.3
4.1 —
4.4
4.5 4.3 Divided into subclauses
4.6 5.1 —
4.7 4.3.7 —
5 5 Divided into subclauses
— 6 New clause
a
See Bibliography.
– 16 – 60440 © IEC:2012
Bibliography
IEC 60027 (all parts), Letter symbols to be used in electrical technology
IEC/TR 60440:1973, Method of measurement of non-linearity in resistors
IEC 60617, Graphical symbols for diagrams
ISO 80000-1, Quantities and units – Part 1: General
Danbridge A/S, “Reliability Testing of Nominally Linear Components by Measuring Third
Harmonic Distortion”, Application Note, 2002
Kühl, R.W. and Ewell, G.J., “Third Harmonic Testing: Current Resistor Applications”,
th
Proceedings, 15 European Passive Components Symposium CARTS-EUROPE 2001,
Copenhagen, Denmark, 2001, pp. 85 - 93.
Kuehl, R.W., “Reliability of thin-film resistors: Impact of third harmonic screening”,
Microelectronics Reliability 42 (2002), pp. 807

____________
– 18 – 60440 © CEI:2012
SOMMAIRE
AVANT-PROPOS . 19
1 Domaine d’application . 21
2 Références normatives . 21
3 Termes et définitions . 21
4 Méthode de mesure . 22
4.1 Principe de mesure . 22
4.2 Circuit de mesure . 24
4.3 Exigences relatives au système de mesure . 25
4.3.1 Fréquence de mesure . 25
4.3.2 Niveau de bruit du système de mesure . 25
4.3.3 Rapport de troisième harmonique du système de mesure . 25
4.3.4 Amplificateur de puissance . 25
4.3.5 Voltmètre . 26
4.3.6 Filtre . 26
4.3.7 Dispositif d'essai . 26
4.4 Vérification du système de mesure . 26
5 Procédure de mesure . 26
5.1 Conditions environnementales . 26
5.2 Préparation du spécimen . 26
5.3 Conditions de mesure . 26
5.4 Procédure . 27
5.5 Précautions . 27
6 Evaluation des résultats de mesure . 27
6.1 Evaluation . 27
6.2 Exigences . 28
7 Informations à fournir dans la spécification applicable au composant . 28
Annexe A (informative) Référence à la CEI/TR 60440 . 32
Bibliographie . 33

Figure 1 – Circuit équivalent à la fréquence fondamentale . 22
Figure 2 – Circuit équivalent à la fréquence de troisième harmonique . 23
Figure 3 – Terme correctif Δ . 24
Figure 4 – Schéma de principe d'un système de mesure adapté . 25

Tableau 1 – Conditions de mesure recommandées (1 de 2) . 30

60440 © CEI:2012 – 19 –
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
MÉTHODE DE MESURE DE LA NON-LINÉARITE DES RÉSISTANCES

AVANT-PROPOS
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