Patent · US Expired

Integrated FM detector including an oscillator having a capacitor and Schmitt trigger

US5274338A · kind A · utility

2Cited by

3References

2Claims

0Family size

Assignee

Deutsche Thomson-Brandt GmbH · DE

Inventors

Martin Rieger · Rottweil, DE
Sabine Roth · Berlin, DE

Key dates

Filing date	Mar 10, 1993
Grant date	Dec 28, 1993
Priority date	—
Expiry date	Mar 10, 2013

Classification

Technology area (CPC H)Electricity
CPC primaryH03D3/24
WIPO fieldBasic communication processes
WIPO sectorElectrical engineering

Abstract

An FM detector for demodulating frequency modulated signals includes an FM detector having an oscillator composed of a capacitor and a Schmitt Trigger. The oscillator is controlled by the input signal to the FM detector. The FM detector also includes a phase detector for mixing the input signal with an oscillator signal from the oscillator to provide an output signal. The frequency of the oscillator is set to the frequency of the input signal using components internal to the FM detector. A first switch is used to charge and discharge the capacitor in accordance with the state of the Schmitt Trigger. A second switch is used to set the frequency of the oscillator to the frequency of the input signal.

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