Apparatus and method for driving LED display
US9286825B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 17, 2013 |
| Grant date | Mar 15, 2016 |
| Priority date | — |
| Expiry date | Feb 28, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2330/06
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The apparatus for driving LED display includes a system control unit having a synchronization signal generator configured to generate a synchronization start signal and a plurality of phase locked loop circuits. Each of the phase locked loop circuits includes a divider coupled to the voltage controlled oscillator and configured to change the sequence of dividing ratios over a modulation period, a sigma delta modulator configured to generate a sequence of random numbers to the divider, and a spread spectrum modulation depth controller coupled to the sigma delta modulator and configured to receive the synchronization start signal from the synchronization signal generator. Upon receipt of the synchronization start signal, the spread spectrum modulation depth controller starts a spread spectrum modulation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.