Operational amplifier and method of operating the operational amplifier
US9431964B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 2014 |
| Grant date | Aug 30, 2016 |
| Priority date | — |
| Expiry date | Jan 17, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45288
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An operational amplifier comprises a first input pair, a second input pair, a switch and a first current mirror. The first input pair comprises a different type of MOS transistor from the second input pair. The switch determines which one of the first or the second input pair is functioning and the operating input pair is configured to output voltage. The switch is further connected to the first input pair and the first current mirror. The first current mirror is further connected to the second input pair, and is configured to copy a current passing through the switch to the second input pair. Therefore an increase of transconductance of the first input pair is compensated by a decrease of transconductance of the second input pair, and the operational amplifier has a substantially constant transconductance no matter which of the first input pair and the second input pair is functioning.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.