Apparatus and method for high efficiency RF power amplification using drain bias adaptation
US7340228B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 2005 |
| Grant date | Mar 4, 2008 |
| Priority date | — |
| Expiry date | Aug 8, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B2001/045
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An RF transmitter having an RF power amplifier comprising: 1) a drive transistor that receives an input RF signal and generates an output RF signal; and 2) a drain bias adaptation circuit for supplying drain current to the drive transistor. The drain bias adaptation circuit comprises: i) a first switch for coupling the drive transistor drain to a system supply voltage; ii) a second switch for coupling the drive transistor drain to a high supply voltage that is greater than the system supply voltage; iii) a first bypass capacitor coupled to the first switch for reducing noise in the drain current when the first switch is closed and the second switch is open; and iv) a second bypass capacitor coupled to the second switch for reducing noise in the drain current when the second switch is closed and the first switch is open.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.