Squelch detection method and circuit using rectifying circuit for detecting out-of-band signal
US8513981B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 12, 2011 |
| Grant date | Aug 20, 2013 |
| Priority date | — |
| Expiry date | Feb 16, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45648
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A circuit for detecting out-of-band signals is disclosed. In one embodiment, the circuit includes a first differential circuit configured to level shift and positively rectify a differential input signal to produce a first output component of a differential output signal. The first differential circuit is further configured to generate and provide a common mode voltage of the differential input signal as a second component of the differential output signal. The circuit further includes a second differential circuit configured to level shift and output first and second fixed voltages based on an input reference voltage and a ground voltage. The circuit is configured to provide the differential output signal and the first and second fixed voltages to an indicator circuit configured to assert an indication responsive to detecting that a differential voltage of the differential output signal is greater than a differential voltage of the first and second fixed voltages.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.