RF variable gain tuned output amplifier which maintains high Q in saturation
US5343162A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 6, 1993 |
| Grant date | Aug 30, 1994 |
| Priority date | — |
| Expiry date | Apr 6, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B2001/0408
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An amplifier with variable gain which maintains high Q when saturated. A resonant circuit is connected between collector outputs of a differential pair of transistors and RF chokes couple DC supply current to the transistors. The chokes have a high impedance at the desired frequency. The emitters of the differential pair of transistors couple together to form a common output which is connected to a current source. The amount of current from the current source substantially controls the gain of the amplifier. Because the resonant circuit is not shunted with a low impedance even when one of the transistors saturates, the Q of the resonant circuit is maintained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.