IEC 62884-3:2018 pdf download

IEC 62884-3:2018 pdf download.Measurement techniques of piezoelectric, dielectric and electrostatic oscillators
1 Scope
This part of IEC 62884 describes the methods for the measurement and evaluation of frequency aging tests of piezoelectric, dielectric and electrostatic oscillators, including Dielectric Resonator Oscillators (DRO) and oscillators using FBAR (hereinafter referred to as “Oscillator”). The purpose of those tests is to provide statistical data supporting aging predictions.
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 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 – Terms, definitions and algorithms IEC 60617, Graphical symbols for diagrams, available at http://std.iec.ch/iec60617 IEC 60679-1, Piezoelectric, dielectric and electrostatic oscillators of assessed qualify – Part 1: Generic specification IEC 62884-1 :201 7, Measurement techniques of piezoelectric, dielectric and electrostatic oscillators – Part 1: Basic methods for the measurement ISO 80000-1, Quantities and units – Part 1: General
3 Terms and definitions, units and symbols
3.1 Terms and definitions For the purposes of this document, the terms and definitions given in IEC 60679-1 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
4 Frequency aging test
4.1 General The test and measurement procedures shall be carried out in accordance with the relevant detail specification. Where any discrepancies occur for any reason, documents shall rank in the following order of precedence: – 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. 4.2 Test and measurement conditions 4.2.1 General General test and measurement conditions refer to IEC 62884-1, and especially the output frequency measurement to 4.5.4 of IEC 62884-1:2017. 4.2.2 Active aging test (non-destructive) Purpose: Statistical verification of aging performance. Unless otherwise specified, the operating oscillator unit shall be maintained at the specified temperature for a continuous period as given in Annex A. During the period of test, the control of temperature and the accuracy of frequency measurement shall be consistent with the accuracy of the maximum frequency variations specified. The oscillator unit shall remain in the chamber throughout the duration of the test and shall be continually supplied with input power, unless otherwise specified. After insertion into the oven, the oscillator shall be allowed to equilibrate with chamber air temperature. Then the oscillator shall be energized and stabilized prior to beginning of and during the measurement acquisition cycle. The stabilization time t stab depends on the type of oscillator as shown in Table 1. The initial frequency f init of the oscillator shall be measured immediately after the stabilization period t stab and thereafter at intervals as shown in Table 1.This approach should only be used if the square root of the least square fit variance of the measurements from the polynomial fit is at least five times smaller than that of the logarithmic fit. The total frequency change and the aging rate at the end of the specified aging period (t = T a ) shall be determined from the fitting equation using the constants determined from the least squares fit. The square root of the least squares fit variance of the measurements from the curve-fit function shall not exceed 5 percent of the total aging change allowed during the test period.