Low noise mixer circuit having passive inductor elements
US5884154A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 1996 |
| Grant date | Mar 16, 1999 |
| Priority date | — |
| Expiry date | Jun 26, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D2200/0084
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A mixer circuit is provided which incorporates inductive elements for low voltage applications. The circuit consists of a balanced amplifier and a switch composed of transistor pairs driven by a local oscillator signal for multiplying the signal to produce a circuit output signal having a predetermined intermediate frequency. Inductors are used to provide degenerative feedback in the balanced amplifier portion of the circuit. The inductors generate negligible noise and produce a negligible dc voltage drop. The transistors in the circuit are thereby maintained in saturation regions of operation as desired. In accordance with another aspect of the invention, an inductor or, alternatively, a parallel inductor-capacitor circuit, is used as a constant current source in conjunction with the input transistors in the balanced amplifier portion of the circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.