Voltage controlled attenuator for multi-band and multi-mode transmitter and method thereof
US6813480B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 19, 2001 |
| Grant date | Nov 2, 2004 |
| Priority date | — |
| Expiry date | May 20, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/04
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The present invention describes a voltage controlled attenuator (VCA) to control an output power level of a radio frequency (RF) signal and to direct the RF signal to an appropriate path for a multi-mode and multi-band radiotelephone without using an external switch and without using multiple common VCAs. The present invention comprises a single differential amplifier and a plurality of steering blocks with each of steering blocks having a path dedicated to a specific RF band and a specific RF mode, having a pair of steering lines to control the RF signal level by having a differential voltage applied, and being capable of being disabled by having its steering lines grounded.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.