Amplifying circuit
US6201442A · kind A · utility
Inventors
Key dates
| Filing date | Sep 25, 1998 |
| Grant date | Mar 13, 2001 |
| Priority date | — |
| Expiry date | Sep 25, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/261
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An amplifier is provided for audio or instrumentation applications which exhibits radically improved performance over existing amplifiers of comparable cost. In a preferred embodiment, the amplifier comprises two operational amplifiers (A.sub.1, A.sub.2) connected in cascade, where feedback elements (Cf.sub.2, Rf.sub.2) are connected across the second op amp (A.sub.2) to cause an intermediate voltage signal (Z) to be substantially advanced in phase. In this embodiment, a capacitor (Cf.sub.1) is also connected across the first op amp (A.sub.1), and an outer DC loop is provided with damping circuitry (Cf.sub.3) to reduce the closed loop gain at high frequencies, stabilizing the combination. The composite amplifier has performance far exceeding a conventional stand-along op amp and is very cheap to construct.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.