Fail-safe photoamplifier circuit with a safety light curtain system
US5266793A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 28, 1992 |
| Grant date | Nov 30, 1993 |
| Priority date | — |
| Expiry date | Apr 28, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F3/087
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A modulated photoamplifier precludes false output signals and oscillations in the event of component failure. The photoamplifier converts modulated electromagnetic energy into voltage pulses. A phototransistor receives the modulated electromagnetic energy and generates corresponding current pulses. A differential amplifier with negative feedback receives the current pulses and produces the corresponding amplified voltage pulses. A capacitor within the feedback network produces optimum gain at the frequency of the modulated electromagnetic energy. A failure of any component within the photoamplifier removes its ability to generate voltage pulses. Therefore, the photoamplifier precludes false output signals and fails to a safe condition in response to the component failure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.