Rail-to-rail input stage circuit with constant transconductance
US9473122B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 2015 |
| Grant date | Oct 18, 2016 |
| Priority date | — |
| Expiry date | Aug 27, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45481
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Embodiments described herein relate to an improved circuit technique in a rail-to-rail input stage circuit utilizing non-complementary differential pairs with bias control designed to maintain a constant transconductance “gm” throughout an input common mode voltage range. The rail-to-rail input stage circuit comprises a first differential pair circuit, a level-shifted differential pair circuit coupled with the first differential pair circuit, and a constant transconductance generation circuit coupled with the level-shifted differential pair circuit. The constant transconductance generation circuit is configured to control the bias current conducting in the level-shifted differential pair circuit based on current conducting in the first differential pair circuit to maintain a constant transconductance in the rail-to-rail input stage circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.