ltp:tfs3x3b

Version 1.0

14-03-2006

Application Note

TFS1575L

1/1

TELEFILTER GmbH

Potsdamer Straße18

D 14 513 TELTOW / Germany

Tel: (+49) 3328 4784-0 / Fax: (+49) 3328 4784-30

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.

1. General

The filter is matched to 50

Ω single ended at input and output.

2. Theoretical matching

The matching element values given below are valid theoretically. The values of the matching

elements are calculated from the input and output terminating impedance.

The termination impedances of the filter are:

input impedance:

80

Ω || 4 pF

output impedance:

80

Ω || 4 pF

L1 = 3,0 nH

L3 = 3,0 nH

L2 = - 2,0 nH

L4 = - 2,0 nH

3.

Matching on PCB ( tfs3x3b ): 1575 MHz

50

Ω test circuit:

L1 = 6,8 nH

L3 = 6,8 nH

L2 = 5,6 nH

L4 = 5,6 nH

If the parasitics on the customer board (mentioned parasitics, additional parasitics of active

parts) are different to this PCB the matching elements have to be slightly adjusted.

In case of questions please contact us to

6

2

1, 3, 4, 5, 7, 8

2

6

2, 3, 4, 6, 7,8

SAW

L1

L2

L4

L3

SAW

L1

L3

L4

L2