Operational amplifier with offset compensation function
US6118395A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 29, 1998 |
| Grant date | Sep 12, 2000 |
| Priority date | — |
| Expiry date | Oct 29, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/804
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An operational amplifier with an offset compensation function and a D/A converter employing the same for eliminating an offset voltage above a certain limit. In the operational amplifier, a current mirror is provided between a high voltage line and first and second nodes, and a current sink is provided between a third node and a low voltage line. A first transistor controls a current amount flowing from the first node to the third node, and a second transistor controls a current amount flowing the second node to the third node. An amplifier is connected between the second node and an output line to amplify a voltage signal of the output line. A mirror controller responds to the voltage signal from the output line to control the second transistor, and a sink controller responds to the voltage signal from the output line to control the current sink.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.