IEC TS 61994-3:2011

Piezoelectric, dielectric and electrostatic devices and associated materials for frequency control, selection and detection - Glossary - Part 3: Piezoelectric and dielectric oscillators

IEC/TS 61994-3:2011(E) specifies the terms and definitions for piezoelectric dielectric oscillators representing the state-of-the-art, which are intended for use in the standards and documents of IEC TC 49.

General Information

• Status: Published
• Publication Date: 25-Jul-2011
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 01.040.31 - Electronics (Vocabularies)
• ICS: 27.040 - Gas and steam turbines. Steam engines
• ICS: 31.140 - Piezoelectric devices
• ICS: 75.120 - Hydraulic fluids
• Technical Committee: TC 49 - Piezoelectric, dielectric and electrostatic devices and associated materials for frequency control, selection and detection
• Drafting Committee: WG 11 - TC 49/WG 11
• Current Stage: DELPUB - Deleted Publication
• Start Date: 20-Dec-2019
• Completion Date: 28-Jan-2021

Relations

• Revised: IEC TS 61994-3:2021 - Piezoelectric, dielectric and electrostatic devices and associated materials for frequency control, selection and detection - Glossary - Part 3: Piezoelectric, dielectric and electrostatic oscillators
• Effective Date: 05-Sep-2023
• Revises: IEC TS 61994-3:2004 - Piezoelectric and dielectric devices for frequency control and selection - Glossary - Part 3: Piezoelectric and dielectric oscillators
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC/TS 61994-3 ®
Edition 2.0 2011-07
TECHNICAL
SPECIFICATION
Piezoelectric, dielectric and electrostatic devices and associated materials for
frequency control, selection and detection – Glossary –
Part 3: Piezoelectric and dielectric oscillators
IEC/TS 61994-3:2011(E)
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by
any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either IEC or
IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,
please contact the address below or your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
et les microfilms, sans l'accord écrit de la CEI ou du Comité national de la CEI du pays du demandeur.
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publication, utilisez les coordonnées ci-après ou contactez le Comité national de la CEI de votre pays de résidence.

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Switzerland
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About IEC publications
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latest edition, a corrigenda or an amendment might have been published.
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IEC/TS 61994-3 ®
Edition 2.0 2011-07
TECHNICAL
SPECIFICATION
Piezoelectric, dielectric and electrostatic devices and associated materials for
frequency control, selection and detection – Glossary –
Part 3: Piezoelectric and dielectric oscillators
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
P
ICS 31.140; 01.040.31 ISBN 978-2-88912-556-2

– 2 – TS 61994-3 © IEC:2011
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
Bibliography . 16

Figure 1 – Characteristics of an output waveform. 6
Figure 2 – Example of the use of frequency offset . 8
Figure 3 – Typical frequency fluctuation characteristics . 10
Figure 4 – Clock signal with phase jitter . 11

TS 61994-3 © IEC:2011 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PIEZOELECTRIC, DIELECTRIC AND
ELECTROSTATIC DEVICES AND ASSOCIATED MATERIALS
FOR FREQUENCY CONTROL, SELECTION AND DETECTION –
GLOSSARY –
Part 3: Piezoelectric and dielectric oscillators

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.
The main task of IEC technical committees is to prepare International Standards. In
exceptional circumstances, a technical committee may propose the publication of a technical
specification when
• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.

– 4 – TS 61994-3 © IEC:2011
IEC 61994-3, which is a technical specification, has been prepared by IEC technical
committee 49: Piezoelectric, dielectric and electrostatic devices and associated materials for
frequency control, selection and detection.
This second edition of IEC 61994-3 cancels and replaces the first edition published in 2004.
This edition constitutes a technical revision.
The main changes with respect to the previous edition are listed below:
– definitions updated,
– terminology given in orderly sequence,
– new terminologies are added,
– drawings inserted for easier understanding.
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
49/928/DTS 49/949/RVC
Full information on the voting for the approval of this technical specification 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 parts of the IEC 61994 series, under the general title Piezoelectric, dielectric and
electrostatic devices and associated materials for frequency control, selection and detection –
Glossary, can be found on the IEC website.
NOTE 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 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
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
TS 61994-3 © IEC:2011 – 5 –
PIEZOELECTRIC, DIELECTRIC AND
ELECTROSTATIC DEVICES AND ASSOCIATED MATERIALS
FOR FREQUENCY CONTROL, SELECTION AND DETECTION –
GLOSSARY –
Part 3: Piezoelectric and dielectric oscillators

1 Scope
This part of IEC 61994 specifies the terms and definitions for piezoelectric dielectric
oscillators representing the state-of-the-art, which are intended for use in the standards and
documents of IEC TC 49.
2 Normative references
Void
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
adjustment frequency
frequency to which an oscillator must be adjusted, under a particular combination of operating
conditions, in order to meet the frequency tolerance specification over the specified range of
operating conditions, i.e. adjustment frequency = nominal frequency + frequency offset
[IEC 60679-1: 2007, 3.2.10]
3.2
Allan variance of fractional frequency fluctuation
unbiased estimate of the preferred definition in the time domain of the short-term stability
characteristic of the oscillator output frequency:
M−1 2
1 (Y −Y )
k+1 k
(τ)≅
σ
y
∑
M−1 2
k=1
where
are the average fractional frequency fluctuations obtained sequentially, with no
Y
k
systematic dead time between measurements;
τ is the sample time over which measurements is averaged;
M is the number of measurements.
NOTE The confidence of the estimate improves as M increases.
[IEC 60679-1: 2007, 3.2.23, modified]
3.3
amplitude modulation distortion
non-linear distortion in which the relative magnitudes of the spectral components of the
modulating signal waveform are modified

– 6 – TS 61994-3 © IEC:2011
NOTE This amplitude modulation distortion is also commonly known as frequency distortion, amplitude distortion
and amplitude/frequency distortion.
[IEC 60679-1: 2007, 3.2.28, modified]
3.4
crystal cut
orientation of the crystal element with respect to the crystallographic axes of the crystal
NOTE This definition is included as it may be desirable to specify the cut (and hence the general form of the
frequency/temperature performance) of a crystal unit used in an oscillator application. The choice of the crystal cut
will imply certain attributes of the oscillator which may not otherwise appear in the detail specification.
[IEC 60679-1: 2007, 3.2.3]
3.5
decay time
fall time
time interval required for the trailing edge of a waveform to change between two defined
levels
NOTE These two defined levels may be the logic levels V and V being at 90 % and 10 %, respectively, of
OH OL
the maximum amplitude (equaling V - V ) of the waveform, or any other ratio as defined in the detail
HI LO
specification (see Figure 1),
where
V is the low level output voltage;
OL
V is the high level output voltage;
OH
V is the upper flat voltage of the pulse waveform;
HI
V is the low flat voltage of the pulse waveform.
LO
[IEC 60679-1: 2007, 3.2.34, modified]

Pulse duration (t )
Pulse duration (t )
(mark)
(space)
V
HI
V upper limit 90 %
OH
Arithmetic mean
of limit
V Lower limit 10 %
OL
V
LO
Time
Decay time
Rise time
IEC  447/07
Figure 1 – Characteristics of an output waveform
3.6
electrostatic discharge
ESD
transfer of electric charge between bodies having different electrostatic potentials in proximity
or through direct contact
Voltage
TS 61994-3 © IEC:2011 – 7 –
[IEC 60050-161:1990, 161-01-22]
3.7
frequency adjustment range
range over which the oscillator frequency may be varied by means of some variable element,
for the purpose of:
a) setting the frequency to a particular value, or
b) to correct the oscillator frequency to a prescribed value after deviation due to ageing, or
other changed conditions
[IEC 60679-1: 2007, 3.2.11]
3.8
frequency/load coefficient
fractional change in output frequency resulting from an incremental change in electrical load
impedance, other parameters remaining unchanged
[IEC 60679-1: 2007, 3.2.20]
3.9
frequency offset
frequency difference, positive or
...

IEC/TS 61994-3 ®
Edition 2.0 2011-07
TECHNICAL
SPECIFICATION
Piezoelectric, dielectric and electrostatic devices and associated materials for
frequency control, selection and detection – Glossary –
Part 3: Piezoelectric and dielectric oscillators

IEC/TS 61994-3:2011(E)
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by

any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either IEC or

IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,
please contact the address below or your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
et les microfilms, sans l'accord écrit de la CEI ou du Comité national de la CEI du pays du demandeur.

Si vous avez des questions sur le copyright de la CEI ou si vous désirez obtenir des droits supplémentaires sur cette

publication, utilisez les coordonnées ci-après ou contactez le Comité national de la CEI de votre pays de résidence.

IEC Central Office
3, rue de Varembé
CH-1211 Geneva 20
Switzerland
Email: [e-mail]
Web: www.iec.ch
About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.
 Catalogue of IEC publications: www.iec.ch/searchpub
The IEC on-line Catalogue enables you to search by a variety of criteria (reference number, text, technical committee,…).
It also gives information on projects, withdrawn and replaced publications.
 IEC Just Published: www.iec.ch/online_news/justpub
Stay up to date on all new IEC publications. Just Published details twice a month all new publications released. Available
on-line and also by email.
 Electropedia: www.electropedia.org
The world's leading online dictionary of electronic and electrical terms containing more than 20 000 terms and definitions
in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical
Vocabulary online.
 Customer Service Centre: www.iec.ch/webstore/custserv
If you wish to give us your feedback on this publication or need further assistance, please visit the Customer Service
Centre FAQ or contact us:
Email: [e-mail]
Tel.: [phone]
Fax: [phone]
IEC/TS 61994-3 ®
Edition 2.0 2011-07
TECHNICAL
SPECIFICATION
Piezoelectric, dielectric and electrostatic devices and associated materials for
frequency control, selection and detection – Glossary –
Part 3: Piezoelectric and dielectric oscillators

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
P
ICS 31.140; 01.040.31 ISBN 978-2-88912-556-2

– 2 – TS 61994-3 © IEC:2011
CONTENTS
FOREWORD . 3

1 Scope . 5

2 Normative references . 5

3 Terms and definitions . 5

Bibliography . 16

Figure 1 – Characteristics of an output waveform. 6

Figure 2 – Example of the use of frequency offset . 8
Figure 3 – Typical frequency fluctuation characteristics . 10
Figure 4 – Clock signal with phase jitter . 11

TS 61994-3 © IEC:2011 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
PIEZOELECTRIC, DIELECTRIC AND
ELECTROSTATIC DEVICES AND ASSOCIATED MATERIALS

FOR FREQUENCY CONTROL, SELECTION AND DETECTION –

GLOSSARY –
Part 3: Piezoelectric and dielectric oscillators

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.
The main task of IEC technical committees is to prepare International Standards. In
exceptional circumstances, a technical committee may propose the publication of a technical
specification when
• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.

– 4 – TS 61994-3 © IEC:2011
IEC 61994-3, which is a technical specification, has been prepared by IEC technical

committee 49: Piezoelectric, dielectric and electrostatic devices and associated materials for

frequency control, selection and detection.

This second edition of IEC 61994-3 cancels and replaces the first edition published in 2004.

This edition constitutes a technical revision.

The main changes with respect to the previous edition are listed below:

– definitions updated,
– terminology given in orderly sequence,

– new terminologies are added,
– drawings inserted for easier understanding.
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
49/928/DTS 49/949/RVC
Full information on the voting for the approval of this technical specification 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 parts of the IEC 61994 series, under the general title Piezoelectric, dielectric and
electrostatic devices and associated materials for frequency control, selection and detection –
Glossary, can be found on the IEC website.
NOTE 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 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
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
TS 61994-3 © IEC:2011 – 5 –
PIEZOELECTRIC, DIELECTRIC AND
ELECTROSTATIC DEVICES AND ASSOCIATED MATERIALS

FOR FREQUENCY CONTROL, SELECTION AND DETECTION –

GLOSSARY –
Part 3: Piezoelectric and dielectric oscillators

1 Scope
This part of IEC 61994 specifies the terms and definitions for piezoelectric dielectric
oscillators representing the state-of-the-art, which are intended for use in the standards and
documents of IEC TC 49.
2 Normative references
Void
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
adjustment frequency
frequency to which an oscillator must be adjusted, under a particular combination of operating
conditions, in order to meet the frequency tolerance specification over the specified range of
operating conditions, i.e. adjustment frequency = nominal frequency + frequency offset
[IEC 60679-1: 2007, 3.2.10]
3.2
Allan variance of fractional frequency fluctuation
unbiased estimate of the preferred definition in the time domain of the short-term stability
characteristic of the oscillator output frequency:
M−1 2
1 (Y −Y )
k+1 k
(τ)≅
σ
y
∑
M−1 2
k=1
where
are the average fractional frequency fluctuations obtained sequentially, with no
Y
k
systematic dead time between measurements;
τ is the sample time over which measurements is averaged;
M is the number of measurements.
NOTE The confidence of the estimate improves as M increases.
[IEC 60679-1: 2007, 3.2.23, modified]
3.3
amplitude modulation distortion
non-linear distortion in which the relative magnitudes of the spectral components of the
modulating signal waveform are modified

– 6 – TS 61994-3 © IEC:2011
NOTE This amplitude modulation distortion is also commonly known as frequency distortion, amplitude distortion

and amplitude/frequency distortion.

[IEC 60679-1: 2007, 3.2.28, modified]

3.4
crystal cut
orientation of the crystal element with respect to the crystallographic axes of the crystal

NOTE This definition is included as it may be desirable to specify the cut (and hence the general form of the

frequency/temperature performance) of a crystal unit used in an oscillator application. The choice of the crystal cut
will imply certain attributes of the oscillator which may not otherwise appear in the detail specification.

[IEC 60679-1: 2007, 3.2.3]
3.5
decay time
fall time
time interval required for the trailing edge of a waveform to change between two defined
levels
NOTE These two defined levels may be the logic levels V and V being at 90 % and 10 %, respectively, of
OH OL
the maximum amplitude (equaling V - V ) of the waveform, or any other ratio as defined in the detail
HI LO
specification (see Figure 1),
where
V is the low level output voltage;
OL
V is the high level output voltage;
OH
V is the upper flat voltage of the pulse waveform;
HI
V is the low flat voltage of the pulse waveform.
LO
[IEC 60679-1: 2007, 3.2.34, modified]

Pulse duration (t )
Pulse duration (t )
(mark)
(space)
V
HI
V upper limit 90 %
OH
Arithmetic mean
of limit
V Lower limit 10 %
OL
V
LO
Time
Decay time
Rise time
IEC  447/07
Figure 1 – Characteristics of an output waveform
3.6
electrostatic discharge
ESD
transfer of electric charge between bodies having different electrostatic potentials in proximity
or through direct contact
Voltage
TS 61994-3 © IEC:2011 – 7 –
[IEC 60050-161:1990, 161-01-22]

3.7
frequency adjustment range
range over which the oscillator frequency may be varied by means of some variable element,

for the purpose of:
a) setting the frequency to a particular value, or

b) to correct the oscillator frequency to a prescribed value after deviation due to ageing, or

other changed conditions
[IEC 60679-1: 2007, 3.2.11]
3.8
frequency/load coefficient
...