RF power amplifier with distributed bias circuit
US6529079B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 2000 |
| Grant date | Mar 4, 2003 |
| Priority date | — |
| Expiry date | Dec 29, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F1/302
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An improved amplifier circuit is disclosed. In one embodiment, the amplifier circuit includes an amplifier transistor that has a base terminal connected to receive an input signal. The amplifier circuit also includes a reference voltage source that generates a reference voltage at a reference voltage output node. A local bias circuit provides a bias voltage to the base terminal of the amplifier transistor. The local bias circuit includes a first transistor that has an emitter terminal coupled to the reference voltage output node, a collector terminal coupled to a supply voltage node, and a base terminal connected to the collector terminal. The local bias circuit also includes a second transistor that has a base terminal coupled to the base terminal of the first transistor, a collector terminal coupled to the supply voltage node, and an emitter terminal coupled to the base terminal of the amplifier transistor. The bias circuit provides a robust, thermally compensated bias voltage to any number of amplifier cells. The bias circuit is ballasted to prevent thermal runaway in any one of the amplifier cells.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.