SAW Components
SAW filter
Short range devices
Series/type:
Ordering code:
B3942
B39171B3942U310
Date:
Version:
November 27, 2012
2.1
EPCOS AG 2012. Reproduction, publication and dissemination of this data sheet, enclosures
hereto and the information contained therein without EPCOS’ prior express consent is prohibited.
SAW Components
B3942
SAW filter
169.5 MHz
Data sheet
Application
■ Low-loss RF filter for smart metering
■ Balanced and unbalanced operation possible
Features
■
■
■
■
■
■
■
■
■
■
Package size 5.0 x 5.0 x 1.35 mm3
Package code QCC8C
RoHS compatible
Approximate weight 0.1 g
Package for Surface Mount Technology
(SMT)
Ni, gold-plated terminals
Lead free soldering compatible with J - STD20C
Passivation layer Elpas
AEC-Q200 qualified component family
Electrostatic Sensitive Device (ESD)
Pin configuration1)
■
■
■
■
■
■
1
2
5
6
4,8
3,7
Input (recommended) or input ground
Input ground (recommended) or input
Output (recommended) or output ground
Output ground (recommended) or output
Ground (case)
to be grounded
1) The recommended pin configuration usually offers best
suppression of electrical crosstalk. The filter characteristics refer to this configuration.
Please read cautions and warnings and
important notes at the end of this document.
2
November 27, 2012
SAW Components
B3942
SAW filter
169.5 MHz
Data sheet
Characteristics
Temperature range for specification:
Terminating source impedance:
Terminating load impedance:
T = –40 ˚C to +85 ˚C
ZS = 50 Ω and matching network
ZL = 50 Ω and matching network
min.
Center frequency
fC
Minimum insertion attenuation
incl. loss in matching elements (QL = 28)
excl. loss in matching elements
αmin
Pass band (relative to αmin)
169.40 ... 169.60 MHz
Relative attenuation (relative to αmin)
αrel
10.00 ... 155.00 MHz
155.00 ... 168.70 MHz
171.40 ... 171.80 MHz
171.80 ... 172.80 MHz
172.80 ... 185.00 MHz
185.00 ... 300.00 MHz
871.65 ... 880.00 MHz
Impedance for pass band matching1)
Input: ZIN = RIN || CIN
Output: ZOUT = ROUT || COUT
1)
max.
—
typ.
@ 25 ˚C
169.5
—
MHz
—
—
1.9
1.3
3.0
2.4
dB
dB
—
0.6
1.8
dB
50
22
16
7
16
44
23
58
28
22
11
22
50
27
—
—
—
—
—
—
—
dB
dB
dB
dB
dB
dB
dB
—
—
670 || 3.6
670 || 3.6
—
—
Ω || pF
Ω || pF
Impedance for passband matching bases on an ideal, perfect matching of the SAW filter to source- and to load
impedance (here 50 Ohm). After removal of the SAW filter the input impedance of the input and output matching network is calculated. The conjugate complex value of these characteristic impedances are the input and
output impedances for flat passband. For more details we refer to EPCOS application note #18.
Please read cautions and warnings and
important notes at the end of this document.
3
November 27, 2012
SAW Components
B3942
SAW filter
169.5 MHz
Data sheet
Maximum ratings
Operable temperature range T
–45/+125 ˚C
Storage temperature range
DC voltage
Source power
–45/+125 ˚C
6
V
10
dBm
Tstg
VDC
PS
Please read cautions and warnings and
important notes at the end of this document.
4
source impedance 50 Ω
November 27, 2012
SAW Components
B3942
SAW filter
169.5 MHz
Data sheet
Matching network to 50 Ω (element values depend on pcb layout and equivalent circuit)
Cp1 = 2.2 pF
Ls2 = 180 nH
Ls3 = 180 nH
Cp4 = 2.2 pF
Minimising the crosstalk
For a good ultimate rejection a low crosstalk is necessary. Low crosstalk can be realised with a good
RF layout. The major crosstalk mechanism is caused by the “ground-loop” problem.
Grounding loops are created if input-and output transducer GND are connected on the top-side of
the PCB and fed to the system grounding plane by a common via hole. To avoid the common
ground path, the ground pin of the input- and output transducer are fed to the system ground plane
(bottom PCB plane) by their own via hole. The transducers’ grounding pins should be isolated from
the upper grounding plane.
A common GND inductivity of 0.5nH degrades the ultimate rejection (crosstalk) by 20dB.
The optimised PCB layout, including matching network for transformation to 50 Ohm, is shown
here. In this PCB layout the grounding loops are minimised to realise good ultimate rejection
Optimised PCB layout for SAW filters in QCC8C package, pinning 1,5 (top side, scale 1:1)
The bottom side is a copper plane (system ground area). The input and output grounding pins are
isolated and connected to the common ground by separated via holes.
For good contact of the upper grounding area with the lower side it is necessary to place enough
via holes.
Please read cautions and warnings and
important notes at the end of this document.
5
November 27, 2012
SAW Components
B3942
SAW filter
169.5 MHz
Data sheet
ESD protection of SAW filters
SAW filters are Electro Static Discharge sensitive devices. To reduce the probability of damages
caused by ESD, special matching topologies have to be applied.
In general, “ESD matching” has to be ensured at that filter port, where electrostatic discharge is
expected.
Electrostatic discharges predominantly appear at the antenna input of RF receivers. Therefore
only the input matching of the SAW filter has to be designed to short circuit or to block the ESD
pulse.
Below two figures show recommended “ESD matching” topologies.
Depending on the input impedance of the SAW filter and the source impedance, the needed
component values have to be determined from case to case.
MLC1
Ls3
Ls3
to output
matching
Lp2
Dp1
Fig. 1 MLC varistor plus ESD matching
to output
matching
Lp2
Fig. 2 Suppressor diode plus ESD matching
In cases where minor ESD occur, following simplified “ESD matching” topologies can be used
alternatively.
Cs1
Ls2
Lp1
to output
matching
Lp2
Fig. 3 shunt L – series L matching
to output
matching
Fig. 4 series C – shunt L matching
Effectiveness of the applied ESD protection has to be checked according to relevant industry
standards or customer specific requirements.
For further information, please refer to EPCOS Application report:
“ESD protection for SAW filters”. This report can be found under www.epcos.com/rke. Click on
“data sheets” and then “Applications” under category “Further information”.
Please read cautions and warnings and
important notes at the end of this document.
6
November 27, 2012
SAW Components
B3942
SAW filter
169.5 MHz
Data sheet
Transfer function
Transfer function (wideband)
Please read cautions and warnings and
important notes at the end of this document.
7
November 27, 2012
SAW Components
B3942
SAW filter
169.5 MHz
Data sheet
Transfer function (ultimate rejection)
Please read cautions and warnings and
important notes at the end of this document.
8
November 27, 2012
SAW Components
B3942
SAW filter
169.5 MHz
Data sheet
References
Type
B3942
Ordering code
B39171B3942U310
Marking and package
C61157-A7-A56
Packaging
F61074-V8230-Z000
Date codes
L_1126
B3942_NB.s2p
S-parameters
B3942_WB.s2p
See file header for port/pin assignment table.
Soldering profile
S_6001
RoHS compatible
RoHS-compatible means that products are compatible with the
requirements according to Art. 4 (substance restrictions) of Directive 2011/65/EU of the European Parliament and of the
Council of June 8th, 2011, on the restriction of the use of certain hazardous substances in electrical and electronic equipment ("Directive") with due regard to the application of exemptions as per Annex III of the Directive in certain cases.
Matching coils
See Inductor pdf-catalog
http://www.tdk.co.jp/tefe02/coil.htm#aname1
and Data Library for circuit simulation
http://www.tdk.co.jp/etvcl/index.htm
For further information please contact your local EPCOS sales office or visit our webpage at
www.epcos.com .
Published by EPCOS AG
Systems, Acoustics, Waves Business Group
P.O. Box 80 17 09, 81617 Munich, GERMANY
EPCOS AG 2012. This brochure replaces the previous edition.
For questions on technology, prices and delivery please contact the Sales Offices of EPCOS AG or
the international Representatives.
Due to technical requirements components may contain dangerous substances. For information on
the type in question please also contact one of our Sales Offices.
Please read cautions and warnings and
important notes at the end of this document.
9
November 27, 2012
Important notes
The following applies to all products named in this publication:
1.
2.
3.
4.
5.
6.
7.
Some parts of this publication contain statements about the suitability of our products for
certain areas of application. These statements are based on our knowledge of typical
requirements that are often placed on our products in the areas of application concerned. We
nevertheless expressly point out that such statements cannot be regarded as binding
statements about the suitability of our products for a particular customer application.
As a rule, EPCOS is either unfamiliar with individual customer applications or less familiar
with them than the customers themselves. For these reasons, it is always ultimately
incumbent on the customer to check and decide whether an EPCOS product with the
properties described in the product specification is suitable for use in a particular customer
application.
We also point out that in individual cases, a malfunction of electronic components or
failure before the end of their usual service life cannot be completely ruled out in the
current state of the art, even if they are operated as specified. In customer applications
requiring a very high level of operational safety and especially in customer applications in
which the malfunction or failure of an electronic component could endanger human life or
health (e.g. in accident prevention or life-saving systems), it must therefore be ensured by
means of suitable design of the customer application or other action taken by the customer
(e.g. installation of protective circuitry or redundancy) that no injury or damage is sustained
by third parties in the event of malfunction or failure of an electronic component.
The warnings, cautions and product-specific notes must be observed.
In order to satisfy certain technical requirements, some of the products described in this
publication may contain substances subject to restrictions in certain jurisdictions (e.g.
because they are classed as hazardous). Useful information on this will be found in our
Material Data Sheets on the Internet (www.epcos.com/material). Should you have any more
detailed questions, please contact our sales offices.
We constantly strive to improve our products. Consequently, the products described in this
publication may change from time to time. The same is true of the corresponding product
specifications. Please check therefore to what extent product descriptions and specifications
contained in this publication are still applicable before or when you place an order.
We also reserve the right to discontinue production and delivery of products. Consequently, we cannot guarantee that all products named in this publication will always be
available. The aforementioned does not apply in the case of individual agreements deviating
from the foregoing for customer-specific products.
Unless otherwise agreed in individual contracts, all orders are subject to the current
version of the “General Terms of Delivery for Products and Services in the Electrical
Industry” published by the German Electrical and Electronics Industry Association
(ZVEI).
The trade names EPCOS, BAOKE, Alu-X, CeraDiode, CeraLink, CSMP, CSSP, CTVS,
DeltaCap, DigiSiMic, DSSP, FilterCap, FormFit, MiniBlue, MiniCell, MKD, MKK, MLSC,
MotorCap, PCC, PhaseCap, PhaseCube, PhaseMod, PhiCap, SIFERRIT, SIFI, SIKOREL,
SilverCap, SIMDAD, SiMic, SIMID, SineFormer, SIOV, SIP5D, SIP5K, ThermoFuse, WindCap
are trademarks registered or pending in Europe and in other countries. Further information
will be found on the Internet at www.epcos.com/trademarks.
10
November 27, 2012