IEC TS 61994-2:2011

IEC/TS 61994-2 ®
Edition 2.0 2011-06
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
Piezoelectric, dielectric and electrostatic devices and associated materials for
frequency control, selection and detection – Glossary –
Part 2: Piezoelectric and dielectric filters

Dispositifs piézoélectriques, diélectriques et électrostatiques et matériaux
associés pour la commande, le choix et la détection de la fréquence –
Glossaire –
Partie 2: Filtres piézoélectriques et diélectriques

IEC/TS 61994-2:2011
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IEC/TS 61994-2 ®
Edition 2.0 2011-06
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
Piezoelectric, dielectric and electrostatic devices and associated materials for
frequency control, selection and detection – Glossary –
Part 2: Piezoelectric and dielectric filters

Dispositifs piézoélectriques, diélectriques et électrostatiques et matériaux
associés pour la commande, le choix et la détection de la fréquence –
Glossaire –
Partie 2: Filtres piézoélectriques et diélectriques

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX R
ICS 31.140; 01.040.31 ISBN 978-2-88912-535-7

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

Figure 1 – Apodized IDT . 6
Figure 2 – Configuration of an interdigital transducer for dispersive filter . 7
Figure 3 – Interdigited interdigital transducer (IIDT) . 9
Figure 4 – Frequency response of Insertion attenuation of a filter . 10
Figure 5 – Configuration of a ladder filter . 10
Figure 6 – Configuration of a lattice filter . 11
Figure 7 – Multiphase transducer (unidirectional transducer) . 12
Figure 8 – Configuration of a resonator filter . 15
Figure 9 – Transversal filter . 18

TS 61994-2  IEC:2011 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PIEZOELECTRIC, DIELECTRIC AND ELECTROSTATIC
DEVICES AND ASSOCIATED MATERIALS
FOR FREQUENCY CONTROL, SELECTION
AND DETECTION – GLOSSARY –
Part 2: Piezoelectric and dielectric filters

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
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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.
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The main task of IEC technical committees is to prepare International Standards. In
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– 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 61994-2  IEC:2011
IEC 61994-2, 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 61994-2 cancels and replaces the first edition published in 2000
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
49/922/DTS 49/931/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 IS0/lEC Directives, Part 2.
A list of all parts of 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
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
___________
The general title is changed from Piezoelectric and dielectric devices for frequency control and selection –
Glossary: to this title based on the change of the title of TC49 in 2009.

TS 61994-2  IEC:2011 – 5 –
PIEZOELECTRIC, DIELECTRIC AND ELECTROSTATIC
DEVICES AND ASSOCIATED MATERIALS
FOR FREQUENCY CONTROL, SELECTION
AND DETECTION – GLOSSARY –
Part 2: Piezoelectric and dielectric filters

1 Scope
This part of IEC 61994 is a technical specification that gives the terms and definitions for
piezoelectric and dielectric filters representing the present state of the art, which are intended
for use in the standards and documents of IEC technical committee 49.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applied. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60050(561):1991, International Electrotechnical Vocabulary (IEV) – Chapter 561:
Piezoelectric devices for frequency control and selection
IEC 60368-1:2000, Piezoelectric filters of assessed quality – Part 1: Generic specification
IEC 60368-2-2:1996, Piezoelectric filters – Part 2: Guide to the use of piezoelectric filters –
Section 2: Piezoelectric ceramic filters
IEC 60862-1:2003, Surface acoustic wave (SAW) filters of assessed quality – Part 1: Generic
specification
IEC 60862-2:2002, Surface acoustic wave (SAW) filters of assessed quality – Part 2:
Guidance on use
IEC 61261-1:1994, Piezoelectric ceramic filters for use in electronic equipment –
A specification in the IEC quality assessment system for electronic components (IECQ) –
Part 1: Generic specification – Qualification approval
IEC 61337-1:2004, Filters using waveguide type dielectric resonators – Part 1: Generic
specification
3 Terms and definitions
For the purposes of this document, the following terms and definitions given in IEC 60050-561
as well as the followings apply.
3.1
apodisation (of an interdigital transducer)
IDT
weighting produced by the change of finger overlap over the length of the IDT
NOTE An apodization of IDT is shown in Figure 1.

– 6 – TS 61994-2  IEC:2011
[IEC 60862-2: 2002, 3.1.18]
IEC  1199/11
Figure 1 – Apodized IDT
3.2
available power
maximum power obtainable from a given source by suitable adjustment of the load impedance
[IEC 60862-1:2003, 2.2.2.35]
3.3
band-pass filter
filter having a single pass band between two specified stop bands
3.4
band-stop filter
filter having a single stop band between two specified pass band
3.5
centre frequency
arithmetic mean of the cut-off frequencies
[IEC 60862-1: 2003, 2.2.2.2]
3.6
comb filter
filter having two or more pass-bands between three or more stop-bands
[IEC 60862-2 :2002, 3.3.5]
3.7
coupling factor for dielectric filters,
k
degree of coupling between two resonators. The coupling between dielectric resonators
is mainly made either magnetically or electrically. According to each case, the equivalent
circuit of coupling is expressed by inductive or capacitive coupling, respectively.
The coupling factor by inductive or capacitive coupling is defined by the following equations
respectively:
k = M / L × L k = C / C × C
m
1 2 1 2
where
, C and L , C are the resonance circuit elements;
L
1 1 2 2
M is the mutual inductance;
is the coupling capacitance;
C
m
k is the coupling factor.
TS 61994-2  IEC:2011 – 7 –
In the case of a symmetric circuit of coupling, the coupling factor can be obtained from two
resonance frequencies calculated or measured for the coupled resonators:
2 2 2 2
k = ( f – f  ) / (f + f )
0 e 0 e
where
f is the resonance frequency in the case of even mode excitation (open-circuited symmetric plane);
e
f is the resonance frequency in the case of odd mode excitation (short-circuited symmetric plane).
The coupling factor of a band-stop filter is the degree of coupling between the resonator and
the transmission line. The coupling factor k is defined as the ratio of the external power loss
(P ) of the resonator system to the internal power loss (P ) of the resonator and can be
e u
expressed by a function of quality factor as follows:
k = P /P = Q /Q = Q /Q – 1
e u u e u L
where
Q is the unloaded quality factor of resonator;
u
Q is the external quality factor of resonator;
e
Q is the loaded quality factor of resonator.
L
[IEC 61337-1: 2004, 2.2.6, modified]
3.8
cut-off frequency
frequency of the pass band at which the relative attenuation of a piezoelectric filter reaches a
specified value
NOTE See Figure 4.
3.9
dispersive filter
filter designed so as to have group delay which is a function of frequency, usually by varying
the finger periodicity
NOTE An interdigital transducer for a dispersive filter is shown in Figure 2.
[IEC 60862-2: 2002, 3.3.4]
l l < l l
2 1
1 2
IEC  1200/11
Figure 2 – Configuration of an interdigital transducer for dispersive filter
3.10
distortion of envelope delay time (in an electrical network)
unwanted variation of the envelope delay time of a signal in an electrical network as a
function of frequency
– 8 – TS 61994-2  IEC:2011
3.11
envelope delay time
time of propagation of a certain characteristic of a signal envelope between two points, for a
certain frequency
3.12
feedthrough signals (signals of electromagnetic interference)
unwanted signals from the input appearing at the filter output due to stray capacitances and
other electromagnetic couplings
[IEC 60862-1: 2003, 2.2.1.29 ]
3.13
feedthrough signal suppression
relative attenuation which implies the suppression of directly coupled signals by the
electromagnetic and electrostatic coupling between the input and output electrodes
[IEC 60862-1: 2003, 2.2.2.27]
3.14
fractional bandwidth (of a band-pass filter)
ratio of the pass bandwidth to the mid-band frequency in the case of band-pass filter
[IEC 61337-1: 2004, 2.2.14, modified]
3.15
fractional bandwidth (of a band-stop filter)
ratio of the stop bandwidth to the mid-band frequency in the case of band-stop filter
[IEC 61337-1: 2004, 2.2.14, modified]
3.16
frequency asymmetrical filter
filter having a specified asymmetrical pass-band or stop-band characteristic in relation to the
reference frequency
[IEC 60862-1: 2003, 2.2.3.3]
3.17
frequency symmetrical filter
filter having a symmetrical frequency characteristic in relation to the reference frequency
[IEC 60862-1: 2003, 2.2.3.2]
3.18
group delay
time equal to the first derivative of the phase shift, in radians, between these points with
respect to the angular frequency
[IEC 60862-1: 2003, 2.2.2.18]
3.19
group delay distortion
difference between the lowest and highest value of group delay in a specified frequency band
[IEC 60862-1: 2003, 2.2.2.19]
TS 61994-2  IEC:2011 – 9 –
3.20
high-pass filter
filter having a single pass band above a cut-off frequency and a stop band for lower
frequencies
3.21
Interdigitated interdigital transducer
IIDT
SAW transducer made of a combination of three or more interdigital transducers. Same as a
multi-interdigital transducer
NOTE 1 An interdigitated interdigital transducer (IIDT) is shown in Figure 3.

In
Out IEC  1201/11
Figure 3 – Interdigited interdigital transducer (IIDT)
NOTE 2 IIDT (or multi-interdigital transducer) resonator filters are referred to as SAW resonator filters composed
of a number of interdigital transduces for input and output in a line alternating with grating reflectors confirming the
interdigital transducer structure at both ends.
[IEC 60862-2 : 2002, 3.1.13]
3.22
input impedance
impedance presented by a filter to the signal source when terminated by a specified load
impedance
3.23
input level
power, voltage or current level applied to the input terminal pair of a filter
[IEC 60862-1: 2003, 2.2.2.29]
3.24
insertion attenuation (of a filter)
ratio, generally expressed in decibels, of the power delivered to the load impedance before
insertion of the filter to the power delivered to the load impedance after insertion of the filter
NOTE An example of frequency responses of filter is shown in Figure 4. In this figure, various insertion
attenuation levels are shown.
– 10 – TS 61994-2  IEC:2011
[IEC 60862-2: 2002, 3.2.6]
Attenuation
Specified
pass band
Group delay
Specified
stop band
Cut-off Centre Reference Cut-off
Frequency
frequency frequency frequency frequency (MHz)
IEC  1202/11
Figure 4 – Frequency response of Insertion attenuation of a filter
3.25
intermodulation distortion
distortion resulting from the combination within the filter of two independent input signals
3.26
ladder filter
filter having a cascade or tandem connection of alternating series and shunt SAW resonators
NOTE A typical ladder filter is shown in Figure 5.
[IEC 60862-2: 2002, 3.3.7]
R1′
R1 R1 R1
R2′ R2 R2 R2
IEC  1203/11
Figure 5 – Configuration of a ladder filter

Attenuation  (dB)
Minimum
Relative
insertion
attenuation
attenuation
TTE ripple
Group delay
distortion
Nominal
insertion
attenuation
Pass-band
ripple
Nominal
group delay
Group delay  (µs)
TS 61994-2  IEC:2011 – 11 –
3.27
lattice filter
filter having at least four SAW resonators connected in series to form a mesh, two
nonadjacent junction points are used as input terminals, while the remaining two junction
points are used as output terminals (bridge circuit).
NOTE Preferably it can used for balanced circuits. A typical lattice filter is shown in Figure 6.
[IEC 60862-2: 2002, 3.3.8]
R1
R2 R2
R1
IEC  1204/11
Figure 6 – Configuration of a lattice filter
3.28
low-pass filter
filter having a single pass band below a cut-off frequency and a stop band for higher
frequencies
3.29
maximum level
power, voltage or current value above which unacceptable distortion of the signal or
irreversible changes may occur in a piezoelectric filter
3.30
mid-band frequency (of a band-pass or band-stop filter)
geometric mean of the cut-off frequencies limiting a single pass band or single stop band
NOTE In practice, the arithmetic mean is often used as a good approximation to the geometric mean for
piezoelectric filters with relatively narrow pass bands or stop bands.
3.31
minimum insertion attenuation
minimum value of insertion attenuation in the pass band (see Figure 4).
[IEC 60862-1: 2003, 2.2.2.13]
3.32
multiphase transducer
interdigital transducer having more than two inputs which are driven in different phases.
Usually used as a unidirectional transducer
NOTE A example of multiphase transducer is shown in Figure 7.
[IEC 60862-2: 2002, 3.1.11]
– 12 – TS 61994-2  IEC:2011
90° phase shifter
SAW forward
IEC  1205/11
Figure 7 – Multiphase transducer (unidirectional transducer)
3.33
nominal frequency
frequency given by the manufacturer or the specification to identify the filter
[IEC 60862-1: 2003, 2.2.2.1]
3.34
nominal group delay
group delay at a specified reference frequency (see Figure 4).
[IEC 60862-1: 2003, 2.2.2.19]
3.35
nominal insertion attenuation
insertion attenuation at a specified reference frequency (see Figure 4).
[IEC 60862-1: 2003, 2.2.2.7]
3.36
nominal level
power, voltage or current level at which the performance measurement is specified
[IEC 60862-1: 2003, 2.2.2.31]
3.37
operable temperature range (of a piezoelectric filter)
range of temperatures over which the piezoelectric filter continues to provide its specified
response characteristics, though not necessarily within the specified tolerances
[IEC 60368-1: 2000, 2.2.43]
3.38
operating temperature range
range of temperatures over which the piezoelectric filter will function maintaining its specified
characteristics within specified tolerances
[IEC 60368-1: 2000, 2.2.42]
3.39
output impedance
impedance presented by the filter to the load when the input is terminated by specified source
impedance
TS 61994-2  IEC:2011 – 13 –
[IEC 60862-1: 2003, 2.2.2.33]
3.40
output level
power, voltage or current level delivered to the load
[IEC 60862-1: 2003, 2.2.2.30]
3.41
pass band
band of frequencies in which the relative attenuation of a piezoelectric filter is equal to, or
less than, a specified value
3.42
pass bandwidth
separation of frequencies between which the attenuation of a piezoelectric filter shall be equal
to, or less than, a specified value
3.43
pass-band ripple (of a filter)
difference between the peak value and the minimum value of attenuation within the pass-band
of a filter
[IEC 60368-1: 2000, 2.2.36]
3.44
pass-band attenuation deviation
maximum variation of the attenuation within a defined portion of the pass-band of a filter
[IEC 60368-1: 2000, 2.2.37]
3.45
phase delay time
time of propagation of a sinusoidal oscillation of a certain frequency between two points
3.46
power flow vector
vector, analogous to a Poynting vector, characterizing energy propagation caused by a
surface acoustic wave
[IEC 60862-2: 2002, 3.1.3]
3.47
power flow angle
angle between the direction of the power flow vector and the direction of the propagation
vector
[IEC 60862-2: 2002, 3.1.5]
3.48
phase distortion (in an electrical network)
unwanted variation of phase difference in an electrical network as a function of frequency

3.49
rated level
power, voltage or current value at which the characteristics of a piezoelectric filter are
specified
– 14 – TS 61994-2  IEC:2011
3.50
reference frequency
frequency defined by the specification to which other frequencies may be referred
[IEC 60862-1: 2003, 2.2.2.3]
3.51
reference temperature
temperature at which certain filter performance parameters are measured, normally
(25 ± 2) °C
[IEC 60368-1: 2000, 2.2.41]
3.52
reflected wave signal suppression
relative attenuation of unwanted signals caused by reflection of SAW or bulk waves from
substrate edges or electrodes within a specified time window
[IEC 60862-1: 2003, 2.2.2.26]
3.53
reflector
SAW reflecting component which normally makes use of the periodic discontinuity provided by
a metal strip array (shorted metal strip aray or open metal strip array ) or a grooved array.
[IEC 60862-2: 2002, 3.1.25, modified]
3.54
reflection coefficient
dimensionless measure of the degree of mismatch between two impedances Z and Z given
a b
Z − Z
a b
by the expression: dB
Z + Z
a b
where
Z and Z represent respectively the input and source impedance or the output and load

a b
impedance
[IEC 60862-1: 2003, 2.2.2.24]
3.55
relative attenuation
difference between the attenuation at a given frequency and the attenuation at the reference
frequency
NOTE See Figure 4.
3.56
resonator filter
filter in which two or more SAW resonators are incorporated
NOTE There are many types of resonator filters. An example of resonator filter is shown in Figure 8.
[IEC 60862-2: 2002, 3.3.6]
TS 61994-2  IEC:2011 – 15 –
IDT
In
Reflector Reflector
Out IEC  1206/11
Figure 8 – Configuration of a resonator filter
3.57
roll-off rate
index describing the rise-up characteristics for digital communication SAW roll-off filters. It is
a ratio of the transition band to the ideal cut-off frequency, which is equal to half of the
sampling frequency, in the case of cosine roll-off frequency characteristics
[IEC 60862-2: 2002, 3.2.25]
3.58
return attenuation
value of the reciprocal of modulus of the reflection coefficient, expressed in decibels.
Z + Z
a b
Quantitatively, it is equal to: 20 log dB
Z − Z
a b
[IEC 60862-1: 2003, 2.2.2.25]
3.59
SAW coupling coefficient
k
s
SAW electromechanical coupling coefficient is defined as follows:
k = 2 ∆v /v
s s s
where
∆v /v is the relative velocity change produced by short-circuiting the surface potential from
s s
the open-circuit condition
[IEC 60862-1, 2003, 2.2.1.8, modified]
3.60
surface acoustic wave filter (SAW filter)
filter characterized by a surface acoustic wave which is usually generated by an interdigital
transducer and propagation along a substrate surface to a receiving transducer
[IEC 60862-2: 2002, 3.1.2]
3.61
SAW beam steering
SAW propagation phenomenon in anisotropic materials described by an angle of power flow
which is not zero
[IEC 60862-2: 2002, 3.1.6]
– 16 – TS 61994-2  IEC:2011
3.62
SAW diffraction
phenomenon (analogous to diffraction of light from a source of finite aperture) which causes
SAW beam spreading and wave-front distortion
[IEC 60862-2: 2002, 3.1.7]
3.63
selectivity
difference between the attenuation at the given frequency outside the pass band and the
reference value at a given reference frequency. The reference frequency might be specified
according to its application
[IEC 60368-2-2: 1996, 3.2.5]
3.64
shape factor (of a band-pass or band-stop filter)
ratio of the two bandwidths of a band-pass or band-stop filter limited by two specified
attenuation values
3.65
shielding electrode
electrode intended for the reduction of electromagnetic interference signals
[IEC 60862-2: 2002, 3.1.32]
3.66
spurious attenuation
attenuation of the largest unwanted response within the specified frequency range, measured
with respect to the reference level
[IEC 61261-1: 1994, 2.1.18]
3.67
spurious reflections
unwanted signals caused by reflection of SAW or bulk waves from substrate edges or
electrodes
[IEC 60862-2: 2002, 3.1.26]
3.68
spurious response
unwanted response of a filter other than that associated with the working frequency
[IEC 61337-1: 2004, 2.2.20, modified]
3.69
spurious response rejection
difference between the maximum level of spurious response and the minimum insertion
attenuation
[IEC 61337-1: 2004, 2.2.21]
3.70
stop band
band of frequencies in which the relative attenuation of a piezoelectric filter is equal to, or
greater than, specified values

TS 61994-2  IEC:2011 – 17 –
3.71
stop bandwidth
separation of frequencies between which the relative attenuation of a piezoelectric filter shall
be equal to, or greater than, a specified value
3.72
storage temperature range
minimum and maximum temperatures as measured on the enclosure at which the
piezoelectric filter may be stored without deterioration or damage to its performance
[IEC 60368-1: 2000, 2.2.44]
3.73
suppression corrugation
grooves in the non-active side of a substrate for suppressing bulk-wave signals
[IEC 60862-2 2002, 3.1.30]
3.74
temperature characteristics of mid-band frequency
maximum reversible variation of mid-band frequency produced over a given temperature
range within the category temperature range. It is expressed normally as a percentage of the
mid-band frequency related to a reference temperature of 25 °C
[IEC 61261-1: 1994, 2.1.11.1, modified]
3.75
temperature coefficient of mid-band frequency
TCF
rate of change of mid-band frequency with the temperature measured over a specified range
–6
of temperature. It is normally expressed in parts per million per degree Celsius (10 /°C)
[IEC 61261-1, 1994, 2.1.11.2, modified]
3.76
temperature cyclic drift of mid-band frequency
maximum irreversible variation of the mid-band frequency observed at room temperature
during or after the completion of a number of specified temperature cycles. It is expressed
normally as a percentage of the mid-band frequency related to the reference temperature -
this is normally 25 °C.
[IEC 61261-1, 1994, 2.1.11.2, modified]
3.77
terminating impedance
either of the impedances presented to the filter by the source or by the load
[IEC 60862-1: 2003, 2.2.2.34]
3.78
total power loss
logarithimic ratio of the available power at the given source to the power that the SAW filter
delivers to a load impedance under specified operating conditions
[IEC 60862-2: 2002, 3.2.5]
3.79
transducer attenuation
logarithmic ratio, expressed in decibels, of the available power of the given source to the
power that the device delivers to a load impedance under specified operating conditions

– 18 – TS 61994-2  IEC:2011
3.80
transducer phase
phase difference between the output of a given filter with a specified load impedance and the
source connected to its input
3.81
transition band
band of frequencies between a cut-off frequency and the nearest point of the adjacent stop
band
3.82
transversal filter
impulse response of a transversal filter is given by the convolution of the impulse response of
the first interdigital transducer with the conjugate complex impulse response of the second
interdigital transducer. The frequency response is given by the Fourier transform of the
impulse response
NOTE An example of simple transversal filter is shown in Figure 9.
[IEC 60862-2: 2002, 3.3.1, modified]

2d
IDT
Input R Output R
s L
Substrate
IEC  1207/11
Figure 9 – Transversal filter
3.83
trap attenuation
relative attenuation at a specified trap frequency
[IEC 60862-1: 2003, 2.2.2.22]
3.84
trap frequency
specified frequency at which the relative attenuation is equal to, or greater than, a specified
value
[IEC 60862-1: 2003, 2.2.2.21]
3.85
triple transit echo
TTE
unwanted signals in a SAW filter which have traversed three times the propagation path
between input and output interdigital transducers caused by reflections from output and input
transducers
[IEC 60862-2: 2002, 3.1.27]
TS 61994-2  IEC:2011 – 19 –
3.86
TTE ripple
maximum variation in attenuation characteristics caused by tte within a specified pass-band

NOTE See Figure 4.
[IEC 60862-2: 2002, 3.2.12]
3.87
unidirectional interdigital transducer
UDT
transducer capable of radiating and receiving surface acoustic waves in or from a single
direction
[IEC 60862-2: 2002, 3.1.10]
3.88
unwanted response
response other than that associated with the mode of vibration intended for the application
[IEC 60862-1: 2003, 2.2.2.28]
___________
– 20 – TS 61994-2  CEI:2011
SOMMAIRE
AVANT-PROPOS . 21
1 Domaine d'application . 23
2 Références normatives . 23
3 Termes et définitions . 23

Figure 1 – TID apodisé . 24
Figure 2 – Configuration d’un transducteur interdigité pour filtre dispersif . 25
Figure 3 – Multi-transducteur interdigité (TIDI) . 27
Figure 4 – Réponse en fréquence de l’affaiblissement d’insertion d’un filtre . 28
Figure 5 – Configuration d’un filtre en échelle . 29
Figure 6 – Configuration d’un filtre en treillis . 29
Figure 7 – Transducteur multiphase (transducteur unidirectionnel) . 30
Figure 8 – Configuration d’un filtre à résonateurs . 33
Figure 9 – Filtre transversal . 37

TS 61994-2  CEI:2011 – 21 –
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
DISPOSITIFS PIÉZOÉLECTRIQUES, DIÉLECTRIQUES ET
ÉLECTROSTATIQUES ET MATÉRIAUX ASSOCIÉS
POUR LA COMMANDE, LE CHOIX ET LA DÉTECTION
DE LA FRÉQUENCE – GLOSSAIRE –
Partie 2: Filtres piézoélectriques et diélectriques

AVANT-PROPOS
1) La Commission Electrotechnique Internationale (CEI) est une organisation mondiale de normalisation
composée de l'ensemble des comités électrotechniques nationaux (Comités nationaux de la CEI). La CEI a
pour objet de favoriser la coopération internationale pour toutes les questions de normalisation dans les
domaines de l'électricité et de l'électronique. A cet effet, la CEI – entre autres activités – publie des Normes
internationales, des Spécifications techniques, des Rapports techniques, des Spécifications accessibles au
public (PAS) et des Guides (ci-après dénommés "Publication(s) de la CEI"). Leur élaboration est confiée à des
comités d'études, aux travaux desquels tout Comité national intéressé par le sujet traité peut participer. Les
organisations internationales, gouvernementales et non gouvernementales, en liaison avec la CEI, participent
également aux travaux. La CEI collabore étroitement avec l'Organisation Internationale de Normalisation (ISO),
selon des conditions fixées par accord entre les deux organisations.
2) Les décisions ou accords officiels de la CEI concernant les questions techniques représentent, dans la mesure
du possible, un accord international sur les sujets étudiés, étant donné que les Comités nationaux de la CEI
intéressés sont représentés dans chaque comité d’études.
3) Les Publications de la CEI se présentent sous la forme de recommandations internationales et sont agréées
comme telles par les Comités nationaux de la CEI. Tous les efforts raisonnables sont entrepris afin que la CEI
s'assure de l'exactitude du contenu technique de ses publications; la CEI ne peut pas être tenue responsable
de l'éventuelle mauvaise utilisation ou interprétation qui en est faite par un quelconque utilisateur final.
4) Dans le but d'encourager l'uniformité internationale, les Comités nationaux de la CEI s'engagent, dans toute la
mesure possible, à appliquer de façon transparente les Publications de la CEI dans leurs publications
nationales et régionales. Toutes divergences entre toutes Publications de la CEI et toutes publications
nationales ou régionales correspondantes doivent être indiquées en termes clairs dans ces dernières.
5) La CEI elle-même ne fournit aucune attestation de conformité. Des organismes de certification indépendants
fournissent des services d'évaluation de conformité et, dans certains secteurs, accèdent aux marques de
conformité de la CEI. La CEI n'est responsable d'aucun des services effectués par les organismes de
certification indépendants.
6) Tous les utilisateurs doivent s'assurer qu'ils sont en possession de la dernière édition de cette publication.
7) Aucune responsabilité ne doit être imputée à la CEI, à ses administrateurs, employés, auxiliaires ou
mandataires, y compris ses experts particuliers et les membres de ses comités d'études et des Comités
nationaux de la CEI, pour tout préjudice causé en cas de dommages corporels et matériels, ou de tout autre
dommage de quelque nature que ce soit, directe ou indirecte, ou pour supporter les coûts (y compris les frais
de justice) et les dépenses découlant de la publication ou de l'utilisation de cette Publication de la CEI ou de
toute autre Publication de la CEI, ou au crédit qui lui est accordé.
8) L'attention est attirée sur les références normatives citées dans cette publication. L'utilisation de publications
référencées est obligatoire pour une application correcte de la présente publication.
9) L’attention est attirée sur le fait que certains des éléments de la présente Publication de la CEI peuvent faire
l’objet de droits de brevet. La CEI ne saurait être tenue pour responsable de ne pas avoir identifié de tels droits
de brevets et de ne pas avoir signalé leur existence.
La tâche principale des comités d’études de la CEI est l’élaboration des Normes
internationales. Exceptionnellement, un comité d’études peut proposer la publication d’une
spécification technique
– lorsqu’en dépit de maints efforts, l’accord requis ne peut être réalisé en faveur de la
publication d’une Norme internationale, ou
– lorsque le sujet en question est encore en cours de développement technique ou quand,
pour une raison quelconque, la possibilité d’un accord pour la publication d’une Norme
internationale peut être envisagée pour l’avenir mais pas dans l’immédiat.
Les spécifications techniques font l’objet d’un nouvel examen trois ans au plus tard après leur
publication afin de décider éventuellement de leur transformation en Normes internationales.

– 22 – TS 61994-2  CEI:2011
La CEI 61994-2, qui est une spécification technique, a été établie par le comité d'études 49
de la CEI: Dispositifs piézoélectriques, diélectriques et électrostatiques et matériaux associés
pour la commande, le choix et la détection de la fréquence.
Cette deuxième édition de la CEI 61994-2 annule et remplace la première édition parue en
2000, dont elle constitue une révision technique.
Les modifications principales par rapport à l’édition antérieure sont les suivantes:
– mise à jour des définitions,
– terminologie donnée selon un schéma bien ordonné,
– ajout de nouvelles terminologies,
– insertion de schémas pour une meilleure compréhension.
Le texte de cette spécification technique est issu des documents suivants:
Projet d’enquête Rapport de vote
49/922/DTS 49/931/RVC
Le rapport de vote indiqué dans le tableau ci-dessus donne toute information sur le vote ayant
abouti à l'approbation de cette spécification technique.
Cette publication a été rédigée selon les Directives ISO/CEI, Partie 2.
Une liste de toutes les parties, présentées sous le titre général Dispositifs piézoélectriques,
diélectriques et électrostatiques et matériaux associés pour la commande, le choix et la
détection de la fréquence – Glossaire, peut être consultées sur le site web de la CEI.
NOTE Les futures normes de cette série porteront dorénavant le nouveau titre général cité ci-dessus. Le titre des
normes existant déjà dans cette série sera mis à jour lors de la prochaine édition.
Le comité a décidé que le contenu de cette publication ne sera pas modifié avant la date d
...