Amplifier input stage with charge pump supplying a differential transistor pair
US5422600A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 1994 |
| Grant date | Jun 6, 1995 |
| Priority date | — |
| Expiry date | Jun 23, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45674
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An input stage to an amplifier circuit (10) operating with a one volt power supply potential (32) receives a differential input signal. A charge pump (36) increases the one volt power supply potential to 1.8 volts for providing additional head-room for the differential input signal. A current source (44) controls a current mirror (40-42) to draw a predetermined current from the charge pump to supply the active conduction path of a differential transistor pair (12-14). An output stage (34) of the amplifier circuit operates off the one volt power supply potential. Since the charge pump drives only the differential transistor pair through the current mirror, it may be made small to fit on the same integrated circuit as the amplifier including any necessary pump capacitors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.