Patent · US Expired

Surface acoustic wave filter having balanced crosstalk capacitances in symmetric operation

US6441704B1 · kind B1 · utility

12Cited by

7References

22Claims

0Family size

Assignee

EPCOS AG · DE

Inventors

Markus Ali-Hackl · Germering, DE
Stefan Freisleben · Neubiberg, DE
Thomas Johannes · Witten, DE
Thomas Baier · Birkenfeld, DE
Ulrich Bauernschmitt · Garching bei München, DE
Ulrike Rösler · Hebertshausen, DE

Key dates

Filing date	Sep 25, 2000
Grant date	Aug 27, 2002
Priority date	—
Expiry date	Nov 8, 2020

Classification

Technology area (CPC H)Electricity
CPC primaryH03H9/6463
WIPO fieldBasic communication processes
WIPO sectorElectrical engineering

Abstract

A surface acoustic wave filter having compensated capacitive and inductive crosstalk between adjacent IDT input and output transducers includes electromagnetically coupled transducers split into partial transducers. The routing of the partial transducer pads is modified such that the flux directions of the magnetic couplings between the adjacent partial transducers are oppositely directed so that the total induced magnetic flux is zero. The partial transducers are connected in series or in parallel such that, in the case of symmetric operation, the crosstalk capacitances between adjacent pads and transducer surfaces are balanced at the corresponding port.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.