Display driver with duty cycle control
US5451979A · kind A · utility
13Cited by
9References
7Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Nov 4, 1993 |
| Grant date | Sep 19, 1995 |
| Priority date | — |
| Expiry date | Nov 4, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G3/32
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A display sign includes a matrix of LED lights which are energized from an unregulated power supply during periodic duty cycles. The duty cycles are adjusted by a programmed microprocessor such that the power supply is not overloaded when a large number of LEDs are energized, and such that excessive power is not applied to the LEDs when a small number of LEDs are energized and the power supply voltage increases.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.