High frequency power amplifier circuit and electric component for high frequency power amplifier
US7271662B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 16, 2005 |
| Grant date | Sep 18, 2007 |
| Priority date | — |
| Expiry date | Mar 7, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03G2201/40
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
In a high frequency power amplifier circuit in which bias voltages are applied to the transistors for amplification by current mirroring, this invention enables preventing waveform distortion near the peak output power level by allowing sufficient idle currents to flow through the transistors for amplification, while enhancing the power efficiency in a low output power region. The power amplifier includes a detection circuit comprising a transistor for detection which receives the AC component of an input signal to the last-stage transistor for amplification at its control terminal, a current mirror circuit which mirrors current flowing through that transistor, and a current-voltage conversion means which converts current flowing in the slave side of the current mirror circuit into a voltage. In the detection circuit, a voltage from a bias circuit for generating the bias voltages for the transistors for amplification is applied to the control terminal of the transistor for detection and output of the detection circuit is applied to the control terminal of the last-stage transistor for amplification.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.