SIST EN 60195:2016
(Main)Method of measurement of current noise generated in fixed resistors (IEC 60195:2016)
Method of measurement of current noise generated in fixed resistors (IEC 60195:2016)
This International Standard specifies a method of measurement and associated test
conditions to assess the "noisiness", or magnitude of current noise, generated in fixed
resistors of any given type. The method applies to all classes of fixed resistors. The aim is to
provide comparable results for the determination of the suitability of resistors for use in
electronic circuits having critical noise requirements.
The current noise in resistive materials reflects the granular structure of the resistive material.
For some resistor technologies utilizing homogenous layers it is regarded as providing an
indication of defects, which are considered as a root cause for abnormal ageing of the
component under the influence of temperature and time.
The method described in this International Standard is not a general specification requirement
and therefore is applied if prescribed by a relevant component specification, or, if agreed
between a customer and a manufacturer.
Messverfahren für das Stromrauschen in Festwiderständen
Méthode pour la mesure du bruit produit en charge par les résistances fixes
L'IEC 60195:2016 spécifie une méthode de mesure et des conditions d'essai associées pour évaluer l'absence de bruit ou l'amplitude du bruit en charge généré dans des résistances fixes d'un type quelconque. La méthode s'applique à toutes les classes de résistances fixes. Elle a pour but de fournir des résultats comparables pour déterminer l'aptitude des résistances utilisées dans des circuits électroniques dont les exigences relatives au bruit sont critiques. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- harmonisation de l'affectation des résistances d'isolement RM dans les conditions de fonctionnement recommandées données dans le Tableau 2;
- correction des valeurs numériques erronées de la contribution du bruit du système, f(T - S) dans le Tableau 3;
- ajout d'un conseil pour prescrire des exigences dans une spécification de composant applicable;
- ajout d'un ensemble de conditions de mesure recommandées pour des spécimens dont la dissipation assignée est inférieure à 100 mW;
- révision éditoriale complète.
Metoda za merjenje tokovnega šuma, ki ga povzročajo stalni upori (IEC 60195:2016)
Ta mednarodni standard določa metodo za merjenje in s tem povezane preskusne pogoje za vrednotenje »šumnosti« ali razsežnosti tokovnega šuma, ki ga povzročajo stalni upori katere koli vrste. Metoda se uporablja za vse razrede stalnih uporov. Cilj je zagotoviti primerljive rezultate za določitev ustreznosti uporov za uporabo v elektronskih vezjih, za katere veljajo zahteve glede kritičnega šuma.
Tokovni šum v uporovnih materialih kaže na zrnato strukturo takšnega materiala. Za nekatere uporovne tehnologije, ki uporabljajo homogene plasti, se upošteva kot pokazatelj napak, ki so obravnavane kot glavni vzrok za neobičajno staranje sestavnega dela pod vplivom temperature in časa.
Metoda, opisana v tem mednarodnem standardu, ni zahteva iz splošne specifikacije, zato se uporablja, če jo predpisuje specifikacija ustreznega sestavnega dela ali se o tem dogovorita kupec in proizvajalec.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 60195:2016
01-oktober-2016
0HWRGD]DPHUMHQMHWRNRYQHJDãXPDNLJDSRY]URþDMRVWDOQLXSRUL ,(&
Method of measurement of current noise generated in fixed resistors (IEC 60195:2016)
Ta slovenski standard je istoveten z: EN 60195:2016
ICS:
17.140.20 Emisija hrupa naprav in Noise emitted by machines
opreme and equipment
31.040.10 Fiksni upor Fixed resistors
SIST EN 60195:2016 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 60195:2016
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SIST EN 60195:2016
EUROPEAN STANDARD EN 60195
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2016
ICS 31.040.10
English Version
Method of measurement of current noise generated in fixed
resistors
(IEC 60195:2016)
Méthode pour la mesure du bruit produit en charge par les Messverfahren für das Stromrauschen in Festwiderständen
résistances fixes (IEC 60195:2016)
(IEC 60195:2016)
This European Standard was approved by CENELEC on 2016-05-12. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2016 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 60195:2016 E
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SIST EN 60195:2016
EN 60195:2016
European foreword
The text of document 40/2431/FDIS, future edition 2 of IEC 60195, prepared by IEC/TC 40
“Capacitors and resistors for electronic equipment" was submitted to the IEC-CENELEC parallel vote
and approved by CENELEC as EN 60195:2016.
The following dates are fixed:
(dop) 2017-02-12
• latest date by which the document has to be
implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2019-05-12
standards conflicting with the
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.
Endorsement notice
The text of the International Standard IEC 60195:2016 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards
indicated:
IEC 60027 (series) NOTE Harmonized as EN 60027 (series).
2
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SIST EN 60195:2016
EN 60195:2016
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1 When an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60068-1 2013 Environmental testing -- Part 1: General EN 60068-1 2014
and guidance
3
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SIST EN 60195:2016
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SIST EN 60195:2016
IEC 60195
®
Edition 2.0 2016-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Method of measurement of current noise generated in fixed resistors
Méthode pour la mesure du bruit produit en charge par les résistances fixes
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.040.10 ISBN 978-2-8322-3272-9
Warning! Make sure that you obtained this publication from an authorized distributor.
Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
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SIST EN 60195:2016
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CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references. 6
3 Terms and definitions . 6
4 Method of measurement . 7
4.1 Noise basics . 7
4.1.1 Noise . 7
4.1.2 Thermal noise . 8
4.1.3 Current noise . 8
4.2 Measurement principle . 9
4.3 Measurement system . 10
4.3.1 Proposal of a suitable measuring system . 10
4.3.2 Alternative measuring systems . 11
4.4 Measurement system requirements . 11
4.4.1 Input circuit . 11
4.4.2 Isolation resistor R . 12
M
4.4.3 DC voltage source . 12
4.4.4 DC electronic voltmeter . 12
4.4.5 Calibration resistor R . 12
Cal
4.4.6 Calibration source . 13
4.4.7 Determination of the calibration voltage . 13
4.4.8 AC band-pass amplifier . 15
4.4.9 AC r.m.s. meter . 16
4.4.10 Test fixture . 16
4.5 Verification of the measuring system . 17
4.5.1 Performance check by measurement of instrument and thermal noise . 17
4.5.2 Performance check by comparison of repeated measurements . 17
5 Measurement procedure . 18
5.1 Ambient conditions . 18
5.2 Preparation of specimen . 18
5.3 Procedure . 18
5.3.1 General . 18
5.3.2 Calibration . 18
5.3.3 Measurement of system noise S . 18
5.3.4 Measurement of total noise T . 19
5.4 Precautions . 22
6 Evaluation of measurement results . 22
6.1 Term for the contribution of system noise . 22
6.2 Determination of the current-noise index A . 24
1
6.3 Determination of the current-noise voltage ratio CNR . 25
U
6.4 Accuracy . 26
6.5 Requirements . 26
7 Information to be given in the relevant component specification . 26
Annex A (informative) Letter symbols and abbreviations . 27
A.1 Letter symbols . 27
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IEC 60195:2016 IEC 2016 – 3 –
A.2 Abbreviations . 27
Annex X (informative) Cross-reference for references to the prior revision of this
standard . 28
Bibliography . 29
Figure 1 – Block schematic of a suitable measuring system . 11
Figure 2 – Typical transfer function of the band-pass amplifier . 16
Figure 3 – Contribution of system noise, f(T – S) . 23
Table 1 – Permissible limits of system noise . 17
Table 2 – Recommended operating conditions (1 of 2) . 20
Table 3 – Numeric values of the contribution of system noise, f(T – S) . 24
st
Table X.1 – Cross reference for references to the 1 edition of this standard . 28
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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
METHOD OF MEASUREMENT OF CURRENT
NOISE GENERATED IN FIXED 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
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
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
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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 60195 has been prepared by IEC technical committee 40:
Capacitors and resistors for electronic equipment.
This second edition cancels and replaces the first edition published in 1965 and constitutes a
technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
• harmonization of the allocation of isolation resistors R in the recommended operating
M
conditions given in Table 2;
• correction of erroneous numeric values of the contribution of system noise, f(T − S) in
Table 3;
• addition of advice on the prescription of requirements in a relevant component
specification;
• addition of a set of recommended measuring conditions for specimens with a rated
dissipation of less than 100 mW;
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IEC 60195:2016 IEC 2016 – 5 –
• complete editorial revision.
The text of this standard is based on the following documents:
FDIS Report on voting
40/2431/FDIS 40/2458/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 website 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.
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METHOD OF MEASUREMENT OF CURRENT
NOISE GENERATED IN FIXED RESISTORS
1 Scope
This International Standard specifies a method of measurement and associated test
conditions to assess the "noisiness", or magnitude of current noise, generated in fixed
resistors of any given type. The method applies to all classes of fixed resistors. The aim is to
provide comparable results for the determination of the suitability of resistors for use in
electronic circuits having critical noise requirements.
The current noise in resistive materials reflects the granular structure of the resistive material.
For some resistor technologies utilizing homogenous layers it is regarded as providing an
indication of defects, which are considered as a root cause for abnormal ageing of the
component under the influence of temperature and time.
The method described in this International Standard is not a general specification requirement
and therefore 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 60068-1:2013, Environmental testing – Part 1: General and guidance
3 Terms and definitions
For the purposes of this document the following terms and definitions apply.
3.1
current-noise
combination of all random fluctuations of current flow in a resistor which are not attributed to
thermal agitation of the charge carriers (thermal noise) and which depend on the applied
direct current
3.2
current-noise index
A
1
logarithmic index of the ratio of the open circuit r.m.s. current-noise voltage in a frequency
decade, in µV, over the d.c. voltage applied under test, in V, used to express the “noisiness”
of an individual resistor
Note 1 to entry: The current-noise index is expressed in dB. The ratio between µV and V is not considered in this
index, leading to its value being 120 dB less than the mathematical current-noise index A ′. This practical index
1
follows the history of prior revisions of this method.
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IEC 60195:2016 IEC 2016 – 7 –
3.3
mathematical current-noise index
A ′
1
logarithmic index of the ratio of the open circuit r.m.s. current-noise voltage in a frequency
decade over the d.c. voltage applied under test, established in consistent units and their
multiples
Note 1 to entry: The mathematical current-noise index is expressed in dB. This index has been introduced for the
mathematical derivation of the considered parameters.
3.4
current-noise voltage ratio
CNR
U
ratio of the open circuit r.m.s. current-noise voltage in a frequency decade over the d.c.
voltage applied under test, established in µV/V, used to express the “noisiness” of an
individual resistor
3.5
flicker noise
pink noise
random fluctuation present in most electronic devices and typically related to internal
properties of the respective device, which depends on direct current and has a power spectral
density inversely proportional to the frequency
3.6
noise
random fluctuation in an electrical signal having instantaneous amplitude values which, due to
their distribution in a random manner, can only be predicted in terms of probability statements
3.7
shot noise
random fluctuation in electric current due to the flowing current consisting of discrete charges,
which is independent of temperature and has nearly constant power spectral density
throughout the frequency spectrum
3.8
thermal noise
random fluctuation generated by the thermal agitation of the charge carriers (usually the
electrons) inside an electrical conductor at equilibrium, which is independent of any applied
voltage and has nearly constant power spectral density throughout the frequency spectrum
Note 1 to entry: Thermal noise is also referred to as Johnson noise or as Nyquist noise.
4 Method of measurement
4.1 Noise basics
4.1.1 Noise
Noise appears as a spontaneous fluctuating voltage e (t) with instantaneous amplitude
n
values.
Noise voltage is a statistically independent random variable, where for most kinds of noise the
frequency distribution of amplitudes follows a Gaussian distribution curve. Therefore noise
voltage cannot be predicted except in terms of probability statements.
Usually the characteristic of principal interest is not the instantaneous amplitude value but the
"time-averaged" value.
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SIST EN 60195:2016
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The measurement of amplitude commonly used and adopted for this International Standard is
the effective (r.m.s.) voltage E observed in a particular frequency pass-band.
n
4.1.2 Thermal noise
The thermal noise of a resistor is a fluctuating voltage caused by the random motion of
thermally agitated charges, which is present in all resistors. The root mean-square value of
the fluctuating voltage appearing at the open-circuit terminals of a resistor, which would be
indicated by the measuring system, may be calculated using Nyquist’s equation:
2
E = e = 4 ⋅ k ⋅T ⋅ R ⋅ ∆f
th th
where
E is the effective voltage (r.m.s. voltage) of the thermal noise in a given bandwidth;
th
e is the momentary voltage of the thermal noise in a given bandwidth;
th
–23
k is the Boltzmann constant, k ≈ 1,38 × 10 J/K;
T is the absolute temperature;
R is the resistance;
∆f is the bandwidth of the effective band-pass filter of the measuring system.
The presence of thermal noise cannot be ignored because the thermal noise of the resistor
under test is frequently a major source of interference in the measurement.
4.1.3 Current noise
The presence of direct current in a fixed resistor causes an increase in the observed total
noise above the level attributed to thermal noise. Regardless of its originating nature, this
excess noise is referred to as current noise.
2 2 2
E = E + E
t th c
where
E is the effective voltage of the total noise in a given bandwidth;
t
E is the effective voltage of the thermal noise in a given bandwidth;
th
E is the effective voltage of the current noise in a given bandwidth.
c
Hence, the current noise is the geometric difference between the total noise and the thermal
noise
2 2 2
E = E − E
c t th
The effective current-noise voltage per 1 Hz bandwidth is substantially inversely proportional
to frequency
2
I
2
[e( f )] ~
f
where
e(f) is the momentary voltage of the current noise as a function of frequency;
I is the d.c. current passing through the resistor;
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IEC 60195:2016 IEC 2016 – 9 –
f is the frequency for which the current noise voltage is considered.
The effective current noise voltage for a given bandwidth is calculated by integrating the
current noise voltage over the frequency band
f
2
2 2
E = [e( f )] df
c
∫
f
1
f
2
2
I
~ df
∫
f
f
1
f
2 2
~ I ln
f
1
where
E is the effective voltage of the current noise in a given bandwidth;
c
f is the lower cut-off frequency of the ideal band-pass;
1
f is the upper cut-off frequency of the ideal band-pass.
2
If the mean-square voltage is inversely proportional to frequency, then ideal rectangular pass-
bands having equal ratios of upper to lower band-pass limits transmit equal amounts of noise
voltage from a given noise source.
A resistor exhibiting current noise may be represented as a noise source having a zero-
impedance current-noise voltage generator connected in series with an independent thermal-
noise voltage generator and with a noise-free resistor.
4.2 Measurement principle
E is, in general, closely proportional to the applied d.c. test voltage
The current noise voltage
c
U . It is recommended, however, to apply a harmonized set of operating conditions in order to
T
ensure the most comparable measurements for all resistors.
Table 2 gives a set of operating conditions recommended for the testing of resistors with
resistances in the range of 100 Ω to 22 MΩ. The values given therein also avoid overloading
the specimen and the input circuit.
The frequency dependence of noise voltages requires the prescription of a frequency pass-
band to be used in this measurement, which is an ideal rectangular pass-band of one
frequency decade, geometrically centered at 1 000 Hz.
The measurement results in the mathematical current noise index in a frequency decade, A ′,
1
as follows:
′
E
′
c
A = 20lg dB
1
U
T
where
E ′ is the effective open circuit current-noise voltage in a frequency decade, given in V;
c
U is the d.c. voltage applied to the resistor under test, given in V.
T
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The typical magnitude of the current-noise voltage being in the microvolt range rather than in
a volt range is reflected in the prevalent current noise index in a frequency decade, A ,
1
E
c
A = 20lg dB
1
U
T
where
E is the effective open circuit current-noise voltage in a frequency decade, given in µV;
c
U is the d.c. voltage applied to the resistor under test, given in V.
T
The ratio between µV and V, which results in an offset of 120 dB, is neglected in the
traditional definition of the current noise index A , hence the following relationship applies:
1
′
A = A − 120 dB .
1 1
Since the current-noise power spectrum approximates to a 1/f frequency characteristic, the
index and the ratio provides an estimate of current noise in any frequency decade.
4.3 Measurement system
4.3.1 Proposal of a suitable measuring system
Figure 1 shows a block schematic of a suitable measuring system.
A three-position switch may be used to access any of the three modes of operation normally
followed in the measurement procedure:
• calibration;
• measurement of system noise;
• measurement of total noise.
The input circuit consists of the resistor under test R , the isolation resistor R and the
T M
calibration resistor R , where the isolation resistor R is required to reduce the shunting
Cal M
effect of the d.c. supply system on the noise generated in the resistor under test.
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IEC 60195:2016 IEC 2016 – 11 –
R
T
3
2
1
R
M
S
U
T
P
U
N rms
V
V
G R
Cal
BPA
IEC
Key
P DC voltage source
G Calibration source, f = 1 kHz
S Three position switch Position 1: Calibration
Position 2: System noise
Position 3: Total noise
R Isolation resistor
M
R Calibration resistor, R = 1 Ω
Cal Cal
R Resistor under test
T
U Test voltage, d.c.
T
BPA Band-pass amplifier with adjustable gain
U Noise voltage, a.c. r.m.s.
N rms
Figure 1 – Block schematic of a suitable measuring system
The following content of this International Standard refers to this suitable measuring system,
unless otherwise specified.
4.3.2 Alternative measuring systems
The proposal of a measuring system in 4.3.1 intends to unify the test and measurement
procedures used for the assessment of the current noise generated in fixed resistors. This
system, however, is not necessarily the only system which can be used, except when
specifically designated as referee or reference methods.
The provider and user of any alternative measuring system shall demonstrate that such
system will give results equivalent to those obtained by the proposed system.
4.4 Measurement system requirements
4.4.1 Input circuit
The input impedance of the measurement system is influenced by the impedance of the d.c.
electronic voltmeter, which is in parallel with the isolation resistor R and also with the
M
resistor under test, and thereby attenuates the noise signal generated in the specimen.
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The input impedance of the d.c. electronic
...
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