Dual-mode control signal generating apparatus
US4371793A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 24, 1981 |
| Grant date | Feb 1, 1983 |
| Priority date | — |
| Expiry date | Apr 24, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/47
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Dual-mode control signal generator, responding to alternative forms of mode selection signal input by generating different arrays of control signal outputs, includes a trio of voltage comparators. In first form, mode selection signal consists of pulse train with DC component of such a magnitude that all signal excursions remain above a reference potential; in second form, DC component magnitude is such that all signal excursions remain below reference potential. In first comparator, comparison of signal with reference potential switches unvarying control current between output current paths in dependence upon form of control signal. In second comparator, comparison of level shifted signal with reference potential results in a pulse train output, but only in presence of first form of selection signal. In third comparator, comparison of oppositely level shifted signal with reference potential results in development of complementary pulse train outputs in presence of second form of selection signal. Intercoupling with first comparator precludes development of outputs by third comparator in presence of first form of selection signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.