MOS transconductance amplifier for active filters
US4823092A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 23, 1987 |
| Grant date | Apr 18, 1989 |
| Priority date | — |
| Expiry date | Jan 23, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45592
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A differential input, differential output transconductor for IC fabrication comprises a matched pair of field-effect transistors (10) whose source terminals (11) are connected together to a first fixed voltage, the substrate terminals are connected together to a second fixed voltage and the quiescent voltages of the gate terminals (12) are equal. The FETs are biassed in the triode region of operation for the expected gate-source voltage and signal voltages of equal but opposite polarity are superimposed on the gate terminals (12) of the FETs. Circuitry is disclosed to maintain the voltage of the drain terminals (13) and to transmit the differential - mode output current component at a higher impedance level to output circuitry. A common-mode bias stabilization circuit, a phase neutralizing circuit and active filter circuits are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.