Integrated instrumentation amplifier for below-ground inputs
US5276405A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 27, 1992 |
| Grant date | Jan 4, 1994 |
| Priority date | — |
| Expiry date | Jul 27, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/261
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An amplifier having a high input dynamic range as well as high CMRR and PSRR values and input impedance while using a single supply voltage, includes an input stage with two transistors which are biased by a constant current, preferably of less than 1 microampere, while the collectors of the transistors are kept at fixed reference voltages. The input signal applied between the emitters of the transistors is transferred to the terminals of a first resistor which is supplied with current from a circuit which mirrors the current into a second resistor, from the terminals of which the output signal is taken. The preferred application is for forming interfaces for lambda probes fitted to catalytic converters for motor vehicles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.