High speed variable gain amplifier
US5717360A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 16, 1996 |
| Grant date | Feb 10, 1998 |
| Priority date | — |
| Expiry date | Apr 16, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F3/45197
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A MOSFET amplifier includes an amplifier stage with a boosted transconductance and a differential current mirror. The amplifier stage with a boosted transconductance includes complementary MOSFETs cross-connected with a fixed current source whereby the drain-to-source current and, therefore, the gate-to-source voltage, of the input MOSFET is fixed by the current source, while the drain-to-source current of the other MOSFET is dependent upon the input signal voltage. The differential current mirror includes a multiple branch differential input stage with a bridging resistor connected between the differential branches. The bridging resistor conducts a bridging current which equals one half of the difference between the differential branch currents, is substantially zero when the differential input voltage is zero and is nonzero when the differential input voltage is nonzero. Variable voltage gain is provided by a serial arrangement of voltage-to-current and current-to-voltage converters with a controllable current gain.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.