SAW filter
Switchable SAW Filter K6257K Application Notes
Author: Updated: Department: Abstract:
Fröhlich 26.08.98 OFW E UE
K625...
Description
Switchable SAW Filter K6257K Application Notes
Author: Updated: Department: Abstract:
Fröhlich 26.08.98 OFW E UE
K6257K is designed for quasi-split-sound, multistandard applications. A BG channel with reduced group delay predistortion and a double nyquist path with flat group delay are selectable. In this application note, a switching circuit with a test layout is proposed and the results are evaluated.
Application note SAW K6257K -1-
OFW E UE
Switchable SAW Filter K6257K - Application Notes
General SAW filter OFW K6257K is designed for Multistandard applications (European standards), except M- and M-related standards. A BG- channel with reduced group delay and a double nyquist path with flat group delay are selectable. It is optimized for video-IF signals, used in combination with Quasisplit sound systems. The filter comes in a flat DIP10K plastic case. Our testboard will help to inform the user. A proposal for a symmetric SAW driver output was worked out. The IF driver of a tuner IC, TUA2007 is used here to provide real conditions on the SAW filter input side. A SAW filters symmetrical output is terminated usually by the differential amplifier of an IF-IC. Here we choose two common collector stages as buffer, the symmetric output is combined by widebandtransformer ( balun) to a practical unsymmetrical output for direct connection to a network analyzer.
The circuit Before the introduction of the switchable SAW filter type, one of a set of two separate SAW filters was s...
Similar Datasheet