1、BRITISH STANDARD BS EN 60444-3:1997 IEC444-3: 1986 Incorporating Amendment No.1 to BS7681-3:1993 (renumbers the BS as BS EN60444-3:1997) Measurement of quartz crystal unit parameters by zero phase technique in a -network Part3: Basic method for the measurement of two-terminal parameters of quartz cr
2、ystal units up to200MHz by phase technique in a -network with compensation of the parallel capacitance C o The European Standard EN60444-3:1997 has the status of a BritishStandard ICS 31.140BSEN60444-3:1997 This BritishStandard, having been prepared under the directionof the Electronic Components St
3、andards Policy Committee, was published underthe authority oftheStandards Board and comes into effect on 15September1993 BSI03-2000 The following BSI references relate to the work on this standard: Committee reference ECL/11 Special announcement in BSINews, May1993 ISBN 0 580 22498 8 Committees resp
4、onsible for this BritishStandard The preparation of this BritishStandard was entrusted by the Electronic Components Standards Policy Committee (ECL/-) to Technical Committee ECL/11, upon which the following bodies were represented: EEA (the Association of Electronics, Telecommunications and Business
5、 Equipment Industries) Electronic Components Industry Federation Institute of Physics Institution of Electrical Engineers Ministry of Defence National Supervising Inspectorate Amendments issued since publication Amd. No. Date Comments 9659 October 1997 BS renumbered as BS EN 60444-3:1997BSEN60444-3:
6、1997 BSI 03-2000 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 1 Scope 3 2 C 0compensation circuit 3 2.1 Electrical specifications 3 2.2 Mechanical specification 5 3 Crystal unit parameters with and without C 0compensation 6 3.1 Series resonance frequency
7、f sand resonance frequency f r 6 3.2 Motional resistance R 1and resonance resistance R r 7 3.3 Motional capacitance C 1and motional inductance L 1 7 4 Test circuit 7 4.1 The ;-network 7 4.2 Accessories of the ;-network 7 4.3 Associated equipment 8 4.4 Compensation circuit 8 5 Method of measurement 8
8、 5.1 Initial calibration of the ;-network 8 5.2 Tuning of the compensation circuit 9 5.3 Frequency and resistance measurement 9 5.4 Evaluation of the motional capacitance C 1and motional inductance L 1 10 Appendix A Analysis of the difference of f, R, C 1and L 1as result ofmeasurementmethods with an
9、d without compensation of C 0 11 Appendix B Additional information on accuracy 12 Appendix C Additional information on circuit components given in Figure 4 a) and Figure 4 b) 13 Figure 1 Equivalent circuit of a crystal unit with compensation of C 0 3 Figure 2 Impedance diagram of a crystal unit with
10、out compensation of parallel capacitance C 0 4 Figure 3 Impedance diagram of a crystal unit when C 0is compensated with a properly tuned compensation network according to Figure 1 5 Figure 4 a) Simplified diagram of the ;-network with electrical adjustment of C 0compensation 6 Figure 4 b) Simplified
11、 diagram of the ;-network with mechanical adjustment of C 0compensation 6 Figure 5 Test circuit 7 Table A.I Typical values for parameters of oscillator crystal units, andthecalculated theoretical differences between parameters increasedwithandwithout compensation 11 List of references Inside back co
12、verBSEN60444-3:1997 ii BSI 03-2000 National foreword This Part of BS EN60444 has been prepared by Technical Committee EPL/49 (formerly ECL/11), and is the English language version of EN60444-3:1997, published by the European Committee for Electrotechnical Standardization (CENELEC). It is identical w
13、ith IEC444-3:1986, Measurement of quartz crystal unit parameters by zero phase technique in a -network Part3: Basic method for the measurement of two-terminal parameters of quartz crystal units up to200MHz by phase technique in a -network with compensation of the parallel capacitance C o , published
14、 by the International Electrotechnical Commission (IEC). Cross references The BritishStandards which implement these international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Inde
15、x”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself co
16、nfer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, theEN title page, pages2 to14, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This
17、will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN60444-3 April1997 ICS 31.140 Descriptors: Quartz crystal units, measurement of parameters, zero phase technique in a pi-network, basic method, two-terminal parameters, compensation
18、of the parallel capacitance, test circuit English version Measurement of quartz crystal unit parameters by zero phase technique in a pi-network Part3: Basic method for the measurement of two-terminal parameters of quartz crystal units up to200MHz by phase technique in a pi-network with compensation
19、of the parallel capacitance C 0 (IEC444-3:1986) Mesure des paramtres des quartz pizolectriques par la technique de phase nulle dans le circuit en pi Partie3: Mthode fondamentale pour la mesure des paramtres deux ples des rsonateurs quartz la frquence jusqu200MHz par la technique de phase dans le cir
20、cuit en pi avec compensation de la capacit parallle C 0 (CEI444-3:1986) Messung von Schwingquarz-Parametern nach dem Null-Phasenverfahren in einem Pi-Netzwerk Teil3: Verfahren zur Messung der Zwei-Pol-Parameter von Schwingquarzen bis200MHz nach dem Phasenverfahren in einem Pi-Netzwerk mit Kompensati
21、on der Parallelkapazitt C 0 (IEC444-3:1986) This European Standard was approved by CENELEC on1997-03-11. 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 altera
22、tion. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by tra
23、nslation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Irel
24、and, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and UnitedKingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 3
25、5, B-1050 Brussels 1997 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref.No.60444-3:1997EEN60444-3:1997 BSI 03-2000 2 Foreword The text of the International Standard IEC444-3:1986, prepared by IEC TC49, Piezoelectric and dielectric devices f
26、or frequency control and selection, was submitted to the formal vote and was approved by CENELEC as EN60444-3 on1997-03-11 without any modification. The following dates were fixed: latest date by which the ENhas to be implemented at national level by publication of an identical national standard or
27、by endorsement (dop)1997-12-01 latest date by which the national standards conflicting with the EN haveto be withdrawn (dow)1997-12-01EN60444-3:1997 BSI 03-2000 3 1 Scope This report specifies a method for the measurement of the parameters of quartz crystal units using an inductance to compensate fo
28、r the effects of C 0at the frequency of the crystal unit with accuracy depending on the type of crystals for: a) frequency with a fractional accuracy ranging between10 6and10 8 ; b) resistance with a fractional accuracy ranging between2% and5%; c) motional capacitance and motional inductance with a
29、fractional accuracy ranging between3% and7%. This report is based on the ;-network described in IEC Publication444-1: Measurement of Quartz Crystal Unit Parameters by Zero Phase Technique in a ;-network, Part1: Basic Method for the Measurement of Resonance Frequency and Resonance Resistance of Quart
30、z Crystal Units by Zero Phase Technique in a ;-network. Essentially new is the compensation of parallel capacitance C 0of the crystal unit by an inductance at the frequency of the crystal unit. In the report, two possible circuits for compensation of C 0are discussed in detail. The compensation circ
31、uits can also be constructed in different ways; for example: with discrete inductance and capacitance or with a resonant line with a moving shorting link. The requirements for the compensation circuit and the measurement method are the same. 2 C 0compensation circuit 2.1 Electrical specifications Cl
32、ose to its resonance frequency a crystal unit can be treated as the circuit of Figure 1, page 3, where the effect of C 0is eliminated by a variable inductor L p . This inductor can be realized by a parallel resonant circuit which may be electronically tuned. The complex impedance Z = R+jX of the unc
33、ompensated crystal unit is given in Figure 2. Figure 2 a) shows the impedance of the crystal unit alone, while Figure 2 b) is for the crystal unit connected in the ;-network. Figure 3 (page 5) shows the impedance of the compensated crystal unit under the same conditions. Figure 1 Equivalent circuit
34、of a crystal unit with compensation of C 0 (The losses of L pare represented by R po )EN60444-3:1997 4 BSI 03-2000 Figure 2 Impedance diagram of a crystal unit without compensation of parallel capacitance C 0EN60444-3:1997 BSI 03-2000 5 The phase angle = Tbetween input and output of a ;-network with
35、 a termination for the crystal unit of resistance2R T =257 is given by: To a first approximation for small values of Tit can be expressed by: As can be seen from Figure 2 and Figure 3 in both cases, there exists a maximum and a minimum phase angle; both are equal in value only for the compensated pa
36、rallel capacitance C 0 . Furthermore the impedance is now symmetric with respect to the series resonance frequency f s . 2.2 Mechanical specification Two possible modifications of the ;-network which meet the requirements of Subclause2.1 are given in Figure 4 a)and Figure 4 b), page 6. Figure 3 Impe
37、dance diagram of a crystal unit when C 0is compensated with aproperlytunedcompensation network according to Figure 1 (1) (2)EN60444-3:1997 6 BSI 03-2000 3 Crystal unit parameters with and without C 0compensation 3.1 Series resonance frequency f sand resonance frequency f r The compensation of C 0per
38、mits the direct measurement at zero phase of the frequency of the series branch whereas IEC Publication444-1 specifies the direct measurement of the resonance frequency by zero phase technique to a first approximation. NOTEAdditional information on circuit components is given in Appendix C. Figure 4
39、 a) Simplified diagram of the ;-network with electrical adjustment of C 0compensation NOTEAdditional information on circuit components is given in Appendix C. Figure 4 b) Simplified diagram of the ;-network with mechanical adjustment of C 0compensation (3)EN60444-3:1997 BSI 03-2000 7 3.2 Motional re
40、sistance R 1and resonance resistance R r The series branch resistance R 1can be calculated from the resistance R 0at zero phase with C 0compensation and the effective resistance R poof the compensation circuit R pois measured slightly below the crystal unit frequency, when the parallel inductance L
41、pis tuned to the parallel capacitance C 0 . The resonance resistance R ris measured directly without compensation. 3.3 Motional capacitance C 1and motional inductance L 1 The motional capacitance C 1and motional inductance L 1can be calculated from phase offset measurements in both cases from equati
42、on (1) of Clause2. This equation can only be solved explicitly from measurements with compensation of C 0 . Without this compensation, equation (2) of Clause2 is often used, with an error which is not negligible at higher frequencies and overtone order. An analysis of the differences in f, R, C 1and
43、 L 1for both cases is given in Appendix A. 4 Test circuit Unlike the circuit diagram shown in Figure1 of IEC Publication444-1, the enclosure is not grounded. Theinternal capacitances to the enclosure are included in the parallel capacitance C 0in order to treat the crystal unit as a two-terminal cir
44、cuit. The compensation inductance L pwith the parallel loss resistance R powhich represents the losses in L pare added according to Figure 1 of Clause2. 4.1 The -network The ;-network of Sub-clause 5.1 of IEC Publication444-1 shall be used. 4.2 Accessories of the -network 4.2.1 Reference resistors A
45、 set of reference resistors used and their performance is given in Sub-clause 5.2.1 of IEC Publication444-1. 4.2.2 Shorting blank The shorting blank is a metal plate with the same dimensions as the reference resistors of Sub-clause4.2.1. (4) NOTE 1The30dB attenuator in channel A may be desirable wit
46、h certain phasemeters and voltmeters. NOTE 2The line stretcher in channel B may be desirable for ease of equalizing the electrical length of the cables. Figure 5 Test circuitEN60444-3:1997 8 BSI 03-2000 4.3 Associated equipment The associated equipment is indicated in Sub-clause 5.3 of IEC Publicati
47、on444-1. 4.4 Compensation circuit 4.4.1 General description An inductance or a parallel resonance circuit with the resulting inductance L pand the losses represented by resistance R poat the crystal frequency is connected in parallel with the crystal unit and the contact plates of the ;-network. The
48、 compensation is performed for the parallel capacitance C 0of the crystal unit and the parasitic capacitance between the contact plates of the ;-network. 4.4.2 Arrangement of wideband compensation circuit As compensation should be used over a wide frequency range, preferably above80MHz, a voltage tu
49、ned parallel inductance connected directly to the contact plates of the ;-network is a convenient solution. The circuit consists basically of a parallel-line inductance and simultaneously tuned shunt capacitors (varactor diodes). The connection points of the compensation circuit to the ;-network are not critical. 4.4.3 Requirements for the compensation circuit for parallel capacitance C 0 4.4.3.1 In the vicinity of the series resonance frequency, the phase of the whole circuit under test (crystal unit
