Amplifier circuit
US6535059B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 22, 2001 |
| Grant date | Mar 18, 2003 |
| Priority date | — |
| Expiry date | May 12, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F1/301
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A reference stage is provided in order to compensate for manufacturing tolerances, for example relating to the threshold voltage of a transistor. This reference stage has a transistor which is a physical equivalent of the transistor to be trimmed in a radio-frequency amplifier stage. In particular, this reference transistor has the same electrical direct current characteristics as the amplifier transistor. A reference voltage can be tapped off across a resistor on the reference stage and can be supplied to a control amplifier which uses this reference voltage to set the operating point of the radio-frequency amplifier transistor such that manufacturing tolerances are compensated for. Such radio-frequency power amplifiers are used, for example, as transmit amplifiers in mobile radios.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.