SAW Components
Data Sheet B3750
SAW Components Low-loss Filter Data Sheet
B3750 433,92 MHz
Ceramic package QCC8C
Features
s RF low-loss filter for remote control receivers s Package for Surface Mounted Technology
(SMT)
s Balanced and unbalanced operation possible s Passivation layer: Protec
Terminals
s Ni, gold plated
typ. dimensions in mm, approx. weight 0,1 g
Pin configuration 1 2 5 6 4,8 3,7 Input Ground Input Output Output Ground Case - Ground to be grounded
Type B3750
Ordering code B39431-B3750-U310
Marking and package according to C61157-A7-A56
Packing according to F61074-V8070-Z000
Electrostactic Sensitive Device (ESD)
Maximum ratings Operable temperature range TA Storage temperature range DC voltage Source power –45/+120 –45/+120 6 10 ˚C ˚C V dBm
Tstg VDC PS
source impedance 50 Ω
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Mar 13, 2003
SAW Components Low-loss Filter Data Sheet
Characteristics Reference temperature: Terminating source impedance: Terminating load impedance:
B3750 433,92 MHz
TA = –40 ... +95˚C ZS = 50 Ω and matching network ZL = 50 Ω and matching network
min. typ. 433,92 max. — MHz
Center frequency (center frequency between 3 dB points)
fC
—
Minimum insertion attenuation αmin (including losses in matching network) 433,76 ... 434,08 MHz Pass band (relative to αmin) 433,76 ... 434,08 MHz 433,74 ... 434,10 MHz 433,70 ... 434,14 MHz Pass bandwidth αrel≤ 3 dB Relative attenuation (relative to αmin) 10,00 ... 414,00 414,00 ... 424,50 424,50 ... 431,72 431,72 ... 432,12 432,12 ... 433,10 434,92 442,00 550,00 700,00 805,00 ... 442,00 ... 550,00 ... 700,00 ... 805,00 ...1000,00 αrel MHz MHz MHz MHz MHz MHz MHz MHz MHz MHz
—
2,0
3,0
dB
— — —
0,5 0,7 1,0
2,0 3,0 6,0
dB dB dB
0,64
0,70
0,76
MHz
55 48 31 39 8 10 36 55 40 60
62 55 35 44 11 14 44 60 45 70
— — — — — — — — — —
dB dB dB dB dB dB dB dB dB dB
Impedance for pass band matching 2) Input: ZIN = RIN || CIN Output: ZOUT = ROUT || COUT
2)
— —
310 || 2,2 310 || 2,2
— —
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 the SAW filter is removed and input impedance into the input matching / 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 #4. 3 Mar 13, 2003
SAW Components Low-loss Filter Data Sheet
Matching network to 50 Ω (element values depend on pcb layout and equivalent circuit)
B3750 433,92 MHz
Ls1 = 39 nH Ls2 = 39 nH
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 2,5 (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.
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Mar 13, 2003
SAW Components Low-loss Filter Data Sheet
Frequency response
B3750 433,92 MHz
Frequency response (wideband)
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Mar 13, 2003
SAW Components Low-loss Filter Data Sheet
Frequency response (ultimate rejection)
B3750 433,92 MHz
Published by EPCOS AG Surface Acoustic Wave Components Division, SAW CE AE PD P.O. Box 80 17 09, D-81617 München © EPCOS AG 2003. All Rights Reserved. Reproduction, publication and dissemination of this brochure and the information contained therein without EPCOS’ prior express consent is prohibited. The information contained in this brochure describes the type of component and shall not be considered as guaranteed characteristics. Purchase orders are subject to the General Conditions for the Supply of Products and Services of the Electrical and Electronics Industry recommended by the ZVEI (German Electrical and Electronic Manufacturers’ Association), unless otherwise agreed. 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.
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