Rail to rail operational amplifier intermediate stage
US5455535A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 3, 1994 |
| Grant date | Oct 3, 1995 |
| Priority date | — |
| Expiry date | Mar 3, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45366
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An interstage circuit functions to combine a first differential voltage and a second differential voltage, the first and second differential voltages being either positive or negative, to produce a current at a single ended output. A first pair of PNP transistors generates a first current corresponding to the first differential voltage, if positive, summed with a first bias current. A first pair of NPN transistors generates a second current corresponding to the second differential voltage, if positive, summed with a second bias current. A second pair of PNP transistors generates a third current corresponding to the first differential voltage, if negative, summed with the second current. A second pair of NPN transistors generates a fourth current corresponding to the second differential voltage, if negative, summed with the first current. The third current is subtracted from the fourth current to produce the current at the single ended output.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.