Ltp: tft038
version 1.0
04.11.2003
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VI
TELEFILTER
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Application Note
TFS 1220 -
1/2
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1. General
The filter is single ended driven. It is matched to 50
Ω
The matching element values given below are valid on our test PCB. If the parasitic’s on the
customer PCB and on this PCB are different, the matching elements have to be optimised
regarding the circuit and PCB design.
The matching elements have been chosen from the E12- series (European standard series
with fixed tolerances).
2. Theoretical matching
The termination impedances of the filter are:
Input impedance:
95
Ω
|| - 0,3 pF
Output impedance:
95
Ω
|| - 0,3 pF
The values of the matching elements which are given below are calculated from the input
and output terminating impedance.
L1
2
6
L2
C1
SAW
C2
1,3,4,5,7,8
L1 = 6.8 nH
C1 = 0.3 pF
L2 = 5.8 nH
C2 = 0.27 pF
TELEFILTER GmbH
Potsdamer Straße 18
D 14 513 TELTOW / Germany
Tel: (+49) 3328 4784-0/ Fax: (+49) 3328 4784-30
E-Mail:
tft@telefilter.com
VI TELEFILTER reserves the right to make changes to the product(s) and/or information contained herein without notice. No liability is
assumed as a result of their use or application. No rights under any patent accompany the sale of any such product(s) or information.
VECTRON [ Vectron International, Inc ]
