Offset correction circuit
US8497733B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 2, 2012 |
| Grant date | Jul 30, 2013 |
| Priority date | — |
| Expiry date | Apr 4, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45534
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The present invention quickly detects an offset and prevents cutoff of low frequency signals. Offset detection circuits smooth an output of a variable gain amplifier at a predetermined time constant and detects the offset, which is a DC component. The detected offset is added to the input of the variable gain amplifier by an adder and the offset in the output of the variable gain amplifier is corrected. The time constant in the offset detection circuit is changed by the resistance values of the variable resistors. Then, the time constant is changed to a small time constant when the gain of the variable gain amplifier is changed and thereafter to a large time constant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.