Precision envelope detector and linear rectifier circuitry
US4194240A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 2, 1978 |
| Grant date | Mar 18, 1980 |
| Priority date | — |
| Expiry date | May 2, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R19/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Disclosed is a method and apparatus for the precise linear rectification and envelope detection of oscillatory signals. The signal is applied to a voltage-to-current converter which supplies current to a constant current sink. The connection between the converter and the sink is also applied through a diode and an output load resistor to a ground connection. The connection is also connected to ground through a second diode of opposite polarity from the diode in series with the load resistor. Very small amplitude voltage signals applied to the converter will cause a small change in the output current of the converter, and the difference between the output current and the constant current sink will be applied either directly to ground through the single diode, or across the output load resistor, dependent upon the polarity. Disclosed also is a full-wave rectifier utilizing constant current sinks and voltage-to-current converters. Additionally, disclosed is a combination of the voltage-to-current converters with differential integrated circuit preamplifiers to boost the initial signal amplitude, and with low pass filtering applied so as to obtain a video or signal envelope output.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.