VECTRON TFS199D_08

Ltp: --10/27/2008
version 1.0
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VI TELEFILTER
Application Note
TFS 199D -
1/1
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1. General
The filter is designed single ended use at the input and at the output.
The terminating impedances are
input:
740 Ω || -7.9pF single ended
output:
880 Ω || -6.2pF single ended
The matching element values given below are calculated from the terminating impedances. If the
values of the matching elements are not equal to standard values the best standard values are given
in brackets. Because these are theoretical values they have to be modified on PCB’s corresponding to
the existing parasitics.
2. Theoretical matching to 50 Ω
The theoretical values of the stated elements are:
L1 = 150 n
L3 = 165 nH (180 nH)
L2 = 164 nH (150 nH)
L4 = 250 nH (220 nH)
L1
L3
10
Input
50 Ohm
5
Output
SAW
L4
L2
50 Ohm
6
1
2,3,4,7,8,9
3.Matching on the PCB
L1= 150nH
L2= 100nH
L3=180nH
L4=100nH
VI TELEFILTER
Potsdamer Straße 18
D 14 513 TELTOW / Germany
Tel: (+49) 3328 4784-52 / Fax: (+49) 3328 4784-30
E-Mail: [email protected]
Vectron International, Inc.
267 Lowell Road
Hudson, NH 03051 / USA
Tel: (603) 598-0070 Fax: (603) 598-0075
E-Mail: [email protected]
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.