Photo-sensor cell suitable for IC chip
US5055668A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 22, 1990 |
| Grant date | Oct 8, 1991 |
| Priority date | — |
| Expiry date | Mar 22, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/943
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The photo-sensor cell comprises two optical flip-flop sensors having two different light intensity thresholds, respectively , under imbalanced load offset conditions, two logic cells for latching only two different binary level signals from the two optical sensor respectively, without latching two of the same binary level signals from the two optical sensors due to a high or low pulsed power supply, and an output logic cell for generating an output binary signal from the time when light intensity rises beyond a higher threshold to the time when it drops below a lower threshold. Since all the elements are standardized in an IC manufacturing process and further no synchronizing clock signals are required between cells and signal processing logic owing to latch operations when a number of cells are connected in series or parallel, it is possible to realize a compact digital photo-sensor cell assembly with hysteresis activated by a pulsed power supply.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.