Low voltage bipolar amplifier
US5436595A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 1, 1994 |
| Grant date | Jul 25, 1995 |
| Priority date | — |
| Expiry date | Aug 1, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/366
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A bipolar transistor amplifier with improved base biasing is disclosed. In the bias circuit of the present invention, the bias current only varies with the log(log) of variations in .beta. of the NPN transistors, making the circuit particularly resistant to temperature and process induced variations in .beta.. A feedback loop also insures that the bias current will remain constant under normal operating conditions. In several embodiments of the present invention, the bias signal and the input signal are kept separate, reducing interference. The amplifier and bias circuit provides a large amount of voltage headroom even with low supply voltages.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.