EN 60679-1:2017

Piezoelectric, dielectric and electrostatic oscillators of assessed quality - Part 1: Generic specification

IEC 60679-1:2017(E) specifies general requirements for piezoelectric, dielectric and electrostatic oscillators, including Dielectric Resonator Oscillators (DRO) and oscillators using FBAR (hereinafter referred to as "Oscillator"), of assessed quality using either capability approval or qualification approval procedures. NOTE Dielectric Resonator Oscillators (DRO) and oscillators using FBAR are under consideration. This edition includes the following significant technical changes with respect to the previous edition: a) the title has been changed; b) additional matters related to oscillator using SAW or MEMS resonator in "Terms, definitions and general information" have been included; c) measurement methods of IEC 60679-1:2007 have been removed (they will be moved to IEC 62884 series); d) the content of Annex A has been extended; e) a new term and definition DIXO (Digital interfaced Crystal Oscillator) has been added; f) a new term and definition SSXO (Spread Spectrum Crystal Oscillator) has been added; g) Annex D has been added.

Piezoelektrische, dielektrische und elektrostatische Oszillatoren mit bewerteter Qualität - Teil 1: Fachgrundspezifikation

Oscillateurs piézoélectriques, diélectriques et électrostatiques sous assurance de la qualité - Partie 1: Spécification générique

L’IEC 60679-1:2017 spécifie les exigences générales relatives aux oscillateurs piézoélectriques, diélectriques et électrostatiques, y compris les oscillateurs à résonateur diélectrique (DRO - Dielectric Resonator Oscillators) et les oscillateurs à résonateurs à ondes acoustiques de volume à couches (FBAR) (ci-après dénommés "Oscillateur"), sous assurance qualité par les procédures d’agrément de savoir-faire ou les procédures d’homologation. NOTE Les oscillateurs DRO et FBAR sont à l’étude. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente: a) le titre a été modifié; b) des éléments supplémentaires relatifs aux oscillateurs utilisant un résonateur OAS ou MEMS ont été ajoutés dans "Termes, définitions et informations générales"; c) les méthodes de mesure de l’IEC 60679-1:2007 ont été supprimées (elles seront intégrées à la série IEC 62884); d) le contenu de l’Annexe A a été enrichi; e) un nouveau terme et sa définition, “DIXO” (digital interfaced crystal oscillator - oscillateur à quartz à interface numérique), ont été ajoutés; f) un nouveau terme et sa définition, “SSXO” (spread spectrum crystal oscillator - oscillateur à quartz à spectre étalé), ont été ajoutés; g) l’Annexe D a été ajoutée.

Piezoelektrični, dielektrični in elektrostatični oscilatorji ocenjene kakovosti - 1. del: Rodovna specifikacija (IEC 60679-1:2017)

Ta del standarda IEC 60679 določa splošne zahteve za piezoelektrične, dielektrične in elektrostatične oscilatorje ocenjene kakovosti, vključno z oscilatorji z dielektričnim resonatorjem (DRO) in oscilatorji, ki uporabljajo resonator FBAR (v nadaljevanju »oscilator«), ki vključujejo postopke za odobritev zmogljivosti ali kvalifikacije.
OPOMBA: Obravnavani so oscilatorji z dielektričnim resonatorjem (DRO) in oscilatorji, ki uporabljajo resonator FBAR.

General Information

• Status: Published
• Publication Date: 16-Nov-2017
• Withdrawal Date: 29-Aug-2020
• ICS: 31.140 - Piezoelectric devices
• Technical Committee: CLC/SR 49 - Piezoelectric and dielectric devices for frequency control and selection
• Drafting Committee: IEC/TC 49 - IEC_TC_49
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 17-Nov-2017
• Completion Date: 17-Nov-2017
• Ref Project: SIST EN 60679-1:2018 - Piezoelectric, dielectric and electrostatic oscillators of assessed quality - Part 1: Generic specification (IEC 60679-1:2017)

Relations

• Replaces: EN 60679-1:2007 - Quartz crystal controlled oscillators of assessed quality - Part 1: Generic specification
• Effective Date: 21-Nov-2017

Overview

EN 60679-1:2017 (IEC 60679-1:2017) is the CLC/CENELEC adoption of the international standard that specifies generic requirements for piezoelectric, dielectric and electrostatic oscillators of assessed quality. It covers a broad class of oscillators - including Dielectric Resonator Oscillators (DRO), FBAR-based oscillators (under consideration), and oscillators using SAW or MEMS resonators - and defines quality assessment routes using capability approval or qualification approval procedures.

This edition updates terminology (adds DIXO - Digital Interfaced Crystal Oscillator - and SSXO - Spread Spectrum Crystal Oscillator), extends annex material (Annex A expanded, new Annex D added), and relocates measurement methods to the IEC 62884 series (measurement techniques).

Key topics and requirements

• Scope and definitions: clear terms for oscillator types (piezoelectric, dielectric, electrostatic), preferred rating values and climatic/vibration categories.
• Quality assessment procedures: two structured approval routes:
  • Capability approval - assesses manufacturer’s production capability and quality systems.
  • Qualification approval - product-level qualification tests and inspections.
• Manufacturing and supply chain controls: rules for primary manufacture, subcontracting, use of incorporated components, and manufacturer approval.
• Test and screening procedures: requirements for test records, screening, rework/repair, release for delivery and validity of approvals (measurement methods relocated to IEC 62884-1 and related documents).
• Annex requirements:
  • Annex A - load circuits and logic-drive guidance (TTL, CMOS, ECL, LVDS).
  • Annex B - latch-up test definition and method.
  • Annex C - electrostatic discharge (ESD) sensitivity classification and test considerations.
  • Annex D - digital interfaced crystal oscillator functions (DIXO).

Applications and who uses it

EN 60679-1:2017 is intended for organizations working with high-reliability frequency sources where assessed quality is required:

• Oscillator manufacturers designing and qualifying piezoelectric, dielectric, FBAR, SAW or MEMS-based oscillators.
• Quality managers & procurement teams specifying assessed-quality components for aerospace, defence, telecom, automotive and industrial instrumentation.
• Test laboratories performing capability or qualification approval testing and record-keeping.
• System integrators and designers needing conformity criteria for clock and timing sources (including digital-interfaced and spread-spectrum crystal oscillators).

Related standards

• IEC 62884 series - measurement techniques for oscillators (now contains detailed measurement methods).
• IEC 60068 series - environmental testing referenced for climatic, vibration and shock categories.
• IEC 60122 / IEC 61019 and other referenced IEC normative documents for component and EMC considerations.

EN 60679-1:2017 is essential when specifying or qualifying reliable timing and frequency-control components (piezoelectric oscillator, dielectric oscillator, electrostatic oscillator) under assessed-quality programs.

Standards Content (Sample)

SLOVENSKI STANDARD
01-januar-2018
1DGRPHãþD
SIST EN 60679-1:2008
3LH]RHOHNWULþQLGLHOHNWULþQLLQHOHNWURVWDWLþQLRVFLODWRUMLRFHQMHQHNDNRYRVWLGHO
5RGRYQDVSHFLILNDFLMD,(&
Piezoelectric, dielectric and electrostatic oscillators of assessed quality - Part 1: Generic
specification (IEC 60679-1:2017)
Ta slovenski standard je istoveten z: EN 60679-1:2017
ICS:
31.140 3LH]RHOHNWULþQHQDSUDYH Piezoelectric devices
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 60679-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2017
ICS 31.140 Supersedes EN 60679-1:2007
English Version
Piezoelectric, dielectric and electrostatic oscillators of assessed
quality - Part 1: Generic specification
(IEC 60679-1:2017)
Oscillateurs piézoélectriques, diélectriques et Piezoelektrische, dielektrische und elektrostatische
électrostatiques sous assurance de la qualité - Partie 1: Oszillatoren mit bewerteter Qualität - Teil 1:
Spécification générique Fachgrundspezifikation
(IEC 60679-1:2017) (IEC 60679-1:2017)
This European Standard was approved by CENELEC on 2017-08-30. 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, Serbia, 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
© 2017 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 60679-1:2017 E
European foreword
The text of document 49/1229/FDIS, future edition 4 of IEC 60679-1, prepared by IEC/TC 49
"Piezoelectric, dielectric and electrostatic devices and associated materials for frequency control,
selection and detection" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN 60679-1:2017.
The following dates are fixed:
(dop) 2018-05-30
• 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) 2020-08-30
standards conflicting with the
document have to be withdrawn
This document supersedes EN 60679-1:2007.

Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice
The text of the International Standard IEC 60679-1:2017 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 60068-2-6 NOTE Harmonized as EN 60068-2-6.
IEC 60068-2-17 NOTE Harmonized as EN 60068-2-17.
IEC 60068-2-27 NOTE Harmonized as EN 60068-2-27.
IEC 60068-2-64 NOTE Harmonized as EN 60068-2-64.
IEC 60122-1:2002 NOTE Harmonized as EN 60122-1:2002 (not modified).
IEC 60679-3:2012 NOTE Harmonized as EN 60679-3:2013 (not modified).
IEC 60679-4 NOTE Harmonized as EN 60679-4.
IEC 60679-5 NOTE Harmonized as EN 60679-5.
IEC 61019-1:2004 NOTE Harmonized as EN 61019-1:2005 (not modified).
IEC 61019-2:2005 NOTE Harmonized as EN 61019-2:2005 (not modified).
IEC 61837-1:2012 NOTE Harmonized as EN 61837-1:2012 (not modified).
IEC 61837-2:2011 NOTE Harmonized as EN 61837-2:2011 (not modified).
IEC 61837-3:2015 NOTE Harmonized as EN 61837-3:2015 (not modified).
IEC 61837-4:2015 NOTE Harmonized as EN 61837-4:2015 (not modified).
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE 1  Where 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 TR 61000-4-1 -  Electromagnetic compatibility (EMC) - Part - -
4-1: Testing and measurement techniques -
Overview of the IEC 61000-4 series
IEC 60027 series Letter symbols to be used in electrical EN 60027 series
technology
IEC 60050-561 -  International electrotechnical vocabulary - - -
Part 561: Piezoelectric, dielectric and
electrostatic devices and associated
materials for frequency control, selection
and detection
IEC 60469 -  Transitions, pulses and related waveforms - EN 60469 -
Terms, definitions and algorithms
IEC 60617 -  Standard data element types with - -
associated classification scheme for electric
components - Part 4: IEC reference
collection for standard data element types
and component classes
IEC 60748-2 -  Semiconductor devices - Integrated circuits - -
Part 2: Digital integrated circuits
IEC 60749-26 -  Semiconductor devices - Mechanical and EN 60749-26 -
climatic test methods - Part 26: Electrostatic
discharge (ESD) sensitivity testing - Human
body model (HBM)
IEC 60749-27 -  Semiconductor devices - Mechanical and EN 60749-27 -
climatic test methods - Part 27: Electrostatic
discharge (ESD) sensitivity testing -
Machine model (MM)
IEC 61340-5-1 -  Electrostatics - Part 5-1: Protection of EN 61340-5-1 -
electronic devices from electrostatic
phenomena - General requirements
IEC 62884-1 2017 Measurement techniques of piezoelectric, EN 62884-1 2017
dielectric and electrostatic oscillators - Part
1: Basic methods for the measurement
ISO 80000-1 -  Quantities and units - Part 1: General EN ISO 80000-1 -

IEC 60679-1 ®
Edition 4.0 2017-07
INTERNATIONAL
STANDARD
Piezoelectric, dielectric and electrostatic oscillators of assessed quality –

Part 1: Generic specification
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.140 ISBN 978-2-8322-4608-5

– 2 – IEC 60679-1:2017 © IEC 2017
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and general information . 7
3.1 General . 7
3.2 Terms and definitions . 7
3.3 Preferred values for ratings and characteristics . 21
3.3.1 General . 21
3.3.2 Climatic category (40/85/56) . 22
3.3.3 Bump severity . 22
3.3.4 Vibration severity . 22
3.3.5 Shock severity . 22
3.3.6 Leak rate . 22
3.4 Marking . 23
3.4.1 General . 23
3.4.2 Packaging. 23
4 Quality assessment procedures . 23
4.1 General . 23
4.2 Primary stage of manufacture . 23
4.3 Structurally similar components . 23
4.4 Subcontracting . 23
4.5 Incorporated components . 24
4.6 Manufacturer’s approval . 24
4.7 Approval procedures . 24
4.7.1 General . 24
4.7.2 Capability approval . 24
4.7.3 Qualification approval . 24
4.8 Procedures for capability approval . 25
4.8.1 General . 25
4.8.2 Eligibility for capability approval . 25
4.8.3 Application for capability approval . 25
4.8.4 Granting of capability approval . 25
4.8.5 Capability manual . 25
4.9 Procedures for qualification approval . 25
4.9.1 General . 25
4.9.2 Eligibility for qualification approval . 25
4.9.3 Application for qualification approval . 25
4.9.4 Granting of qualification approval . 25
4.9.5 Quality conformance inspection . 26
4.10 Test procedures . 26
4.11 Screening requirements . 26
4.12 Rework and repair work . 26
4.12.1 Rework . 26
4.12.2 Repair work . 26
4.13 Certified test records. 26
4.14 Validity of release . 26
4.15 Release for delivery . 26

IEC 60679-1:2017 © IEC 2017 – 3 –
4.16 Unchecked parameters . 27
Annex A (normative) Load circuit for logic drive . 28
A.1 TTL and Schottky . 28
A.2 CMOS . 30
A.3 ECL . 30
A.4 LVDS . 31
Annex B (normative) Latch-up test . 32
B.1 Definition . 32
B.1.1 Latch-up . 32
B.1.2 Test procedure . 32
B.2 Test method . 32
Annex C (normative) Electrostatic discharge sensitivity classification . 33
C.1 Definition . 33
C.1.1 Electrostatic discharge (ESD) . 33
C.1.2 Test procedure . 33
C.2 Test methods . 33
C.2.1 General . 33
C.2.2 Leaded oscillator . 33
C.2.3 SMD oscillator . 33
C.2.4 The impact of ESD on Oscillator in steady-state . 33
Annex D (normative) Digital interfaced crystal oscillator’s function . 34
Bibliography . 35

Figure 1 – Basic configurations of SAW resonators . 9
Figure 2 – Example of the use of frequency offset. 11
Figure 3 – Linearity of frequency modulation deviation . 16
Figure 4 – Characteristics of an output waveform . 18
Figure 5 – Definition of start-up time . 19
Figure 6 – Clock signal with period jitter. 19
Figure 7 – Phase jitter measures . 20
Figure 8 – Gaussian distribution of jitter . 20
Figure 9 – Jitter amplitude and period of jitter frequency . 20
Figure 10 – Jitter tolerance according to ITU-T G.825, ATIS-0900101, Telcordia GR-
253 and ETSI EN 300 462 . 21
Figure A.1 – Circuit for TTL . 28
Figure A.2 – Circuit for Schottky logic . 29
Figure A.3 – Circuit for PECL . 30
Figure A.4 – Circuit for LVDS . 31

Table A.1 – Values to be used when calculating R and R . 30
1 2
Table A.2 – Operating condition . 31
Table A.3 – DC Electrical characteristics output load = 50 Ω to Vcc-2V . 31
Table D.1 – Function of the digital interface . 34

– 4 – IEC 60679-1:2017 © IEC 2017
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PIEZOELECTRIC, DIELECTRIC AND ELECTROSTATIC
OSCILLATORS OF ASSESSED QUALITY –

Part 1: Generic specification
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 60679-1 has been prepared by IEC technical committee TC 49:
Piezoelectric, dielectric and electrostatic devices and associated materials for frequency
control, selection and detection.
This fourth edition cancels and replaces the third edition published in 2007. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the title has been changed;
b) additional matters related to oscillator using SAW or MEMS resonator in "Terms,
definitions and general information" have been included;
c) measurement methods of IEC 60679-1:2007 have been removed (they will be moved to
IEC 62884 series);
IEC 60679-1:2017 © IEC 2017 – 5 –
d) the content of Annex A has been extended;
e) a new term and definition DIXO (Digital interfaced Crystal Oscillator) has been added;
f) a new term and definition SSXO (Spread Spectrum Crystal Oscillator) has been added;
g) Annex D has been added.
The text of this standard is based on the following documents:
FDIS Report on voting
49/1229/FDIS 49/1233/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 60679 series, published under the general title piezoelectric,
dielectric and electrostatic oscillators of assessed quality 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 document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

– 6 – IEC 60679-1:2017 © IEC 2017
PIEZOELECTRIC, DIELECTRIC AND ELECTROSTATIC
OSCILLATORS OF ASSESSED QUALITY –

Part 1: Generic specification
1 Scope
This part of IEC 60679 specifies general requirements for piezoelectric, dielectric and
electrostatic oscillators, including Dielectric Resonator Oscillators (DRO) and oscillators using
FBAR (hereinafter referred to as "Oscillator"), of assessed quality using either capability
approval or qualification approval procedures.
NOTE Dielectric Resonator Oscillators (DRO) and oscillators using FBAR are under consideration.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
IEC 60027 (all parts), Letter symbols to be used in electrical technology
IEC 60050-561, International electrotecnical vocabulary – Part 561: Piezoelectric, dielectric
and electrostatic devices and associated materials for frequency control, selection and
detection. Available at www.electropedia.org
IEC 60469, Transitions, pulses and related waveforms – Terms, definitions and algorithms
IEC 60617, Graphical symbols for diagrams. Available at http://std.iec.ch/iec60617
IEC 60748-2, Semiconductor devices – Integrated circuits – Part 2: Digital integrated circuits
IEC 60749-26, Semiconductor devices – Mechanical and climatic test methods – Part 26:
Electrostatic discharge (ESD) sensitivity testing – Human body model (HBM)
IEC 60749-27, Semiconductor devices – Mechanical and climatic test methods – Part 27:
Electrostatic discharge (ESD) sensitivity testing – Machine model (MM)
IEC TR 61000-4-1, Electromagnetic compatibility (EMC) – Part 4-1: Testing and measurement
techniques – Overview of the IEC 61000-4 series
IEC 61340-5-1, Electrostatics – Part 5-1: Protection of electronic devices from electrostatic
phenomena – General requirements
IEC 62884-1:2017, Measurement techniques of piezoelectric, dielectric, and electrostatic
oscillators – Part 1: Basic methods for the measurement
ISO 80000-1, Quantities and units – Part 1: General
Where any discrepancies occur for any reason, documents shall rank in the following order of
precedence:
IEC 60679-1:2017 © IEC 2017 – 7 –
• detail specification;
• sectional specification;
• generic specification;
• any other international documents (for example of the IEC) to which reference is made.
The same order of precedence shall apply to equivalent national documents.
3 Terms, definitions and general information
3.1 General
Units, graphical symbols, letter symbols and terminology shall, wherever possible, be taken
from the following standards:
• IEC 60027;
• IEC 60050-561;
• IEC 60469;
• IEC 60617;
• ISO 80000-1.
3.2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.2.1
simple packaged crystal oscillator
SPXO
crystal controlled oscillator having no means of temperature control or compensation,
exhibiting a frequency/temperature characteristic determined substantially by the quartz
crystal resonator employed
[SOURCE: IEC 60050-561:2014, 561-03-30]
3.2.2
overtone crystal controlled oscillator
oscillator designed to operate with the controlling piezoelectric resonator functioning in a
specified mechanical overtone order of vibration
[SOURCE: IEC 60050-561:2014, 561-03-20, modified – The word "functioning" has been
added.]
3.2.3
crystal cut
orientation of the crystal element with respect to the crystallographic axes of the crystal
Note 1 to entry: It can 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.
[SOURCE: IEC 60050-561:2014, 561-03-04]

– 8 – IEC 60679-1:2017 © IEC 2017
3.2.4
voltage controlled crystal oscillator
VCXO
crystal controlled oscillator, the frequency of which can be deviated or modulated according to
a specific relation, through application of a control voltage
[SOURCE: IEC 60050-561:2014, 561-03-41]
3.2.5
temperature compensated crystal oscillator
TCXO
crystal controlled oscillator whose frequency deviation due to temperature is reduced by
means of a compensation system, incorporated in the device
[SOURCE: IEC 60050-561:2014, 561-03-36]
3.2.6
oven controlled crystal oscillator
OCXO
crystal controlled oscillator in which at least the piezoelectric resonator is temperature
controlled
Note 1 to entry: This mode of operation ensures that the oscillator frequency will remain sensibly constant over
the operating temperature range of the OCXO, therefore independent of the frequency/temperature characteristic
of the crystal unit.
[SOURCE: IEC 60050-561:2014, 561-03-19, modified – The note to entry has been added.]
3.2.7
surface acoustic wave
SAW
acoustic wave, propagating along the surface of an elastic substrate, the amplitude of which
decays exponentially with substrate depth
[SOURCE: IEC 60050-561:2014, 561-01-86]
3.2.8
SAWR
surface acoustic wave resonator
SAW resonator
resonator using multiple reflections of surface acoustic waves
[SOURCE: IEC 60050-561:2014, 561-01-87, modified – The term "SAW resonator" has been
added.]
3.2.9
one-port SAW resonator
SAW resonator having a pair of terminals
SEE: Figure 1a.
[SOURCE: IEC 60050-561:2014, 561-01-57, modified – The figure reference has been
changed.]
3.2.10
two-port SAW resonator
SAW resonator having input and output ports
SEE: Figure 1b
IEC 60679-1:2017 © IEC 2017 – 9 –
[SOURCE: IEC 60050-561:2014, 561-01-94, modified – The figure reference has been
changed.]
IEC
a) One-port resonator with opened array
IEC
b) Two-port resonator with shorted arrays
Figure 1 – Basic configurations of SAW resonators
3.2.11
SAW oscillator
oscillator that uses a SAW resonator as the main frequency controlling element
3.2.12
simple packaged SAW oscillator
SPSO
SAW oscillator having no means of temperature control or compensation, exhibiting a
frequency/temperature characteristic determined substantially by SAW resonator employed
[SOURCE: IEC 60050-561:2014, 561-03-30, modified – change from crystal oscillator to SAW
oscillator and from crystal resonator to SAW resonator.]
3.2.13
voltage controlled SAW oscillator
VCSO
SAW oscillator, the frequency of which can be deviated or modulated according to a specific
relation, through application of a control voltage
[SOURCE: IEC 60050-561:2014, 561-03-41, modified – change from crystal resonator to SAW
oscillator.]
– 10 – IEC 60679-1:2017 © IEC 2017
3.2.14
temperature compensated SAW oscillator
TCSO
SAW oscillator whose frequency deviation due to temperature is reduced by means of a
compensation system incorporated in the device
[SOURCE: IEC 60050-561:2014, 561-03-36, modified – change from crystal resonator to SAW
oscillator.]
3.2.15
electrostatic micro electro mechanical system oscillator
electrostatic MEMS oscillator
oscillator that uses a MEMS device as the main frequency controlling element
3.2.16
voltage controlled electrostatic MEMS oscillator
electrostatic MEMS oscillator, the frequency of which can be deviated or modulated according
to a specified relation, by application of a control voltage
[SOURCE: IEC 60050-561:2014, 561-03-41, modified – change from crystal to MEMS
oscillator.]
3.2.17
digital interfaced crystal oscillator
DIXO
crystal oscillator, the frequency and the functions of which can be controlled, by application of
an external digital signal
Note 1 to entry: It will be combined as DI-TCXO in TCXO and as DI-OCXO in OCXO.
3.2.18
spread spectrum crystal oscillator
SSXO
crystal oscillator that reduces the peak of frequency spectrum by modulating the oscillation
frequency
3.2.19
nominal frequency
frequency given by the manufacturer or the specification to identify the oscillator
[SOURCE: IEC 60050-561:2014, 561-02-31, modified – The word "filter" has been replaced
by" oscillator".]
3.2.20
frequency tolerance
maximum permissible deviation of a specified characteristic frequency from the specified
value due to a specific cause, or a combination of causes
Note 1 to entry: Frequency tolerances are often assigned separately to specified ambient effects, namely
electrical, mechanical and environmental. When this approach is used, it is necessary to define the values of other
operating parameters as well as the range of the specified variable, that is to say:
– deviation from the frequency at the specified reference temperature due to operation over the specified
temperature range, other conditions remaining constant;
– deviation from the frequency at the specified supply voltage due to supply voltage changes over the specified
range, other conditions remaining constant;
– deviation from the initial frequency due to ageing, other conditions remaining constant;
– deviation from the frequency with specified load conditions due to changes in load impedance over the
specified range, other conditions remaining constant.

IEC 60679-1:2017 © IEC 2017 – 11 –
In some cases, an overall frequency tolerance may be specified, due to any/all combinations of operating
parameters, during a specified lifetime.
[SOURCE: IEC 60050-561:2014, 561-01-33, modified – Note 1 to entry has been added.]
3.2.21
frequency offset
frequency difference, positive or negative, which should be added to the specified nominal
frequency of Oscillator, when adjusting the Oscillator frequency under a particular set of
operating conditions in order to minimize its deviation from nominal frequency over the
specified range of operating conditions
Note 1 to entry: In order to minimize the frequency deviation from nominal over the entire temperature range, a
frequency offset may be specified for adjustment at the reference temperature (see Figure 2).
F(T) with offset =ΔF at 25 °C
ΔF
Nominal Frequency
F(T) with zero offset
Adjustment temperature
–20 °C 70 °C
25 °C
ΔF
-ΔF
–20°C
25°C
70°C
Operating temperature during adjustment
IEC
Figure 2 – Example of the use of frequency offset
[SOURCE: IEC 60050-561:2014, 561-03-09]
3.2.22
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
Note 1 to entry: Adjustment frequency corresponds to nominal frequency plus frequency offset.
Frequency offset
Frequency
– 12 – IEC 60679-1:2017 © IEC 2017
[SOURCE: IEC 60050-561:2014, 561-03-01]
3.2.23
frequency adjustment range
range over which 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 oscillator frequency to a prescribed value after deviation due to ageing, or other
changed conditions
Note 1 to entry: For test procedures – see 4.5.11 of IEC 62884-1:2017.
[SOURCE: IEC 60050-561:2014, 561-04-1003-07, modified – Note 1 to entry has been added.]
3.2.24
storage temperature range
minimum and maximum temperatures as measured on the enclosure at which an oscillator
may be stored without deterioration or damage to its performance
[SOURCE: IEC 60050-561:2014, 561-02-67, modified – The word "the device" has been
replaced by "an oscillator".]
3.2.25
operating temperature range,
range of temperatures over which the oscillator will function, maintaining frequency and other
output signal characteristics within specified tolerances
[SOURCE: IEC 60050-561:2014, 561-03-18]
3.2.26
operable temperature range
range of temperatures over which the oscillator will continue to provide an output signal,
though not necessarily within the specified tolerances of frequency, level, waveform, etc.
[SOURCE: IEC 60050-561:2014, 561-01-58, modified – Some elements and specifications
have been changed from resonator to Oscillator.]
3.2.27
reference temperature
temperature at which certain Oscillator performance parameters are measured
Note 1 to entry: The reference temperature is normally 25 °C ± 2 °C.
[SOURCE: IEC 60050-561:2014, 561-03-25]
3.2.28
reference point temperature
temperature measured at a specific reference point relative to an oscillator
[SOURCE: IEC 60050-561:2014, 561-03-24]
3.2.29
thermal transient frequency stability
oscillator frequency time response when ambient temperature is changed from one specified
temperature to another with a specific rate
[SOURCE: IEC 60050-561:2014, 561-03-37]

IEC 60679-1:2017 © IEC 2017 – 13 –
3.2.30
stabilization time
duration, measured from the initial application of power, required for an oscillator to stabilize
its operation within specified limits
Note 1 to entry: For test procedures – see 4.5.10 of IEC 62884-1:2017.
[SOURCE: IEC 60050-561:2014, 561-03-33, modified – Note 1 to entry has been added.]
3.2.31
frequency/temperature characteristics
deviation from the frequency at the specified reference temperature due to operation over the
specified temperature range, other conditions remaining constant
Note 1 to entry: For test procedures – see 4.5.5 of IEC 62884-1:2017.
3.2.32
frequency/temperature stability
maximum permissible deviation of the oscillator frequency, with no reference implied, due to
operation over the specified temperature range at nominal supply and load conditions,
other conditions constant
( f − f )
max min
f − T = ±
stability
( f + f )
max min
where
f is the maximum frequency measured during the temperature run,
max
f is the minimum frequency measured during the temperature run
min
Note 1 to entry: For test procedures – see 4.5.5 of IEC 62884-1:2017 .
[SOURCE: MIL-PRF-55310E w/Amendment 2:2014]
3.2.33
frequency/voltage coefficient
fractional change in output frequency resulting from an incremental change in supply voltage,
other parameters remaining unchanged
Note 1 to entry: In the case of OCXOs, a considerable time may elapse before the full effect of a supply voltage
change is observed, as the temperature of the oven may drift gradually to a new value following the voltage
perturbation.
Note 2 to entry: For test procedures – see 4.5.7 of IEC 62884-1:2017.
[SOURCE: IEC 60050-561:2014, 561-03-11, modified – Note 2 to entry has been added.]
3.2.34
frequency/load coefficient
fractional change in output frequency resulting from an incremental change in electrical load
impedance, other parameters remaining unchanged
Note 1 to entry: For test procedures – see 4.5.6 of IEC 62884-1:2017.
[SOURCE: IEC 60050-561:2014, 561-03-08, modified – Note 1 to entry has been added.]
3.2.35
long-term frequency stability
frequency ageing
relationship between oscillator frequency and time

– 14 – IEC 60679-1:2017 © IEC 2017
Note 1 to entry: This long-term frequency drift that is caused by secular changes in the crystal unit and/or other
elements of the oscillator circuit, and should be expressed as fractional change in mean frequency per specified
time interval.
[SOURCE: IEC 60050-561:2014, 561-03-16]
3.2.36
short-term frequency stability
random fluctuations of the frequency of Oscillator over short periods of time
[SOURCE: IEC 60050-561:2014, 561-03-29]
3.2.37
Allan variance AVAR of fractional frequency fluctuation
AVAR of fractional frequency fluctuation
unbiased estimate of the preferred definition in the time domain of the short-term stability
characteristic of Oscillator output frequency:
M −1
2 2
σ (τ ) ≅ (Y − Y )
y ∑ k +1 k
2(M −1)
k =1
where
Y are the average fractional frequency fluctuations obtained sequentially, with no
k
systematic dead time between measurements;
τ is the sample time over which measurements are averaged;
M is the number of measurements.
Note 1 to entry: The confidence of the estimate improves as M increases.
[SOURCE: IEC 60050-561:2014/AMD1:2016, 561-03-02, modified – The second preferred
term has been added.]
3.2.38
Allan deviation of fractional frequency fluctuation
ADEV of fractional frequency fluctuation
measure in the time domain of the short-term frequency stability of Oscillator, based on the
statistical properties of a number of frequency measurements, each representing an average
of the frequency over the specified sampling interval τ
Note 1 to entry: The preferred measure of fractional frequency fluctuation is:
M −1 2
 
σ (τ ) ≅  (Y − Y ) 
y k+1 k
∑
2(M − 1)
 
k=1
 
3.2.39
phase noise
frequency-domain measure of the short-term frequency stability of Oscillator
Note 1 to entry: This phase noise is normally expressed as the power spectral density of the phase fluctuations,
S (f), where the phase fluctuation function φ(t) is expressed as;
ϕ
1 dφ(t)
= F(t) − F
2π dt
The spectral density of phase fluctuation can be directly related to the spectral density of
frequency fluctuation by
IEC 60679-1:2017 © IEC 2017 – 15 –
 F 
 
S ( f ) = S ( f ) [rad /Hz]
φ y
 
f
 
Where
F(t) is the instantaneous oscillator frequency
F is the average oscillator frequency
f is the Fourier frequency
Note 2 to entry: For test procedures – see 4.5.25 of IEC 62884-1:2017.
[SOURCE: IEC 60050-561:2014, 561-03-22 modified – Note 1 to entry has been modified and
Note 2 to entry has been added.]
3.2.40
spectral purity
measure of frequency stability in the frequency domain
Note 1 to entry: This spectral purity is usually represented as the signal side noise power spectrum expressed in
decibels relative to total signal power, per hertz bandwidth. This spectral purity includes non-deterministic noise
power, harmonic distortion components and spurious single frequency interferences.
Note 2 to entry: For test procedures – see 4.5.29 of IEC 62884-1:2017.
[SOURCE: IEC 60050-561:2014, 561-03-31, modified – Note 2 to entry has been added.]
3.2.41
incidental frequency modulation
optional measure of frequency stability in the frequency domain
Note 1 to entry: Incidental frequency modulation is best described in terms of the spectrum of the resultant base-
band signal obtained by applying Oscillator signal to an ideal discriminator circuit of specified characteristics. lf the
detection bandwidth is adequately specified, the incidental frequency modulation may be expressed as a fractional
–8
proportion of the output frequency (for example 2×10 r.m.s. in a 10 kHz band).
Note 2 to entry: For test procedures – see 4.5.30 of IEC 62884-1:2017.
[SOURCE: IEC 60050-561:2014, 561-03-13, modified – The existing Note 1 and Note 2 have
been merged into Note 1 and a new Note 2 to entry has been
...