Amplifier with active bias compensation and method for adjusting quiescent current
US6046642A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 8, 1998 |
| Grant date | Apr 4, 2000 |
| Priority date | — |
| Expiry date | Sep 8, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45638
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An active bias compensation circuit (110) senses a quiescent current flowing in an amplifier (130) and adjusts the quiescent current to maintain an optimal DC biasing of the amplifier (130) over a wide range of factors, e.g., temperature variation, process variation, history of the amplifier (130), etc. The compensation circuit (110) includes two transistors (101, 102) forming a difference amplifier. A sensing voltage proportional to the quiescent current and a reference voltage are applied to the base electrodes of the two transistors (101, 102), which generates a bias signal in response to a difference between the sensing voltage and the reference voltage. The bias signal adjusts the quiescent current in the amplifier (130).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.