Single-ended input to differential output amplifier with integral two-pole filter
US5049831A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 29, 1990 |
| Grant date | Sep 17, 1991 |
| Priority date | — |
| Expiry date | Mar 29, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H11/1217
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A single-ended input to differential output amplifier performs a predetermined transfer function on an input signal substantially independently of nonlinearities in component values. The input signal and a first reference voltage are coupled to a circuit network, which is coupled to a fully differential operational amplifier, to implement the predetermined transfer function. A common mode voltage between positive and negative output signals of the operational amplifier is sensed and fed back to the operational amplifier so that the operational amplifier may set the common mode voltage to a second reference voltage. The circuit network has first, second, and third capacitors, the third capacitor coupled between a positive input terminal and the first reference voltage. To reduce circuit area, the third capacitor is coupled between a positive input terminal and the negative output terminal of the operational amplifier, allowing either the first capacitor or the second capacitor to be halved in size to again implement the predetermined transfer function.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.