Isolation amplifier with high linearity
US4191929A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 5, 1978 |
| Grant date | Mar 4, 1980 |
| Priority date | — |
| Expiry date | Jun 5, 1998 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F3/393
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A transformer-coupled isolation amplifier which can accept signals over a wide dynamic range while maintaining very high linearity. An input signal is applied to an input winding of a transformer. The secondary winding of the isolation transformer is connected across the differential inputs of a high-gain amplifier. Negative feedback is provided around the amplifier so that the transformer secondary winding is connected across a virtual short; and the negative feedback tends to drive the voltage applied to the inputs of the amplifier to a very small value. The negative feedback from the amplifier induces a current in the transformer secondary which cancels the flux produced by current flowing in the primary, thereby reducing the effects of non-linearities in the BH curve of the transformer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.