Impedance converter circuit
US6577139B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 6, 2001 |
| Grant date | Jun 10, 2003 |
| Priority date | — |
| Expiry date | Dec 13, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H11/28
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An impedance converter module has a phase reversal circuit to receive a 2-wire excitation signal at first and second terminals, and to provide a polarized excitation signal with a predetermined polarity based on the 2-wire excitation signal. A series current path has a sense resistor connected in series with a variable impedance source. The polarized excitation signal is applied across the series current path. An output-voltage-sense circuit provides an output-voltage-sense signal based on a voltage across the series current path. A current mirror provides a drive signal to a ratiometric device based on current flowing through the series current path. Differential amplifiers receive a ratiometric response signal from the ratiometric device, and output measurement signals based on the ratiometric signal. A summing node combines the measurement signals to provide a single-ended ratiometric signal. The variable impedance source is controlled to provide a two-wire response signal at the 2-wire terminals based on the single-ended ratiometric signal and the output-voltage-sense signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.