Drive circuit of capacitive load and integrated circuit for driving capacitive load
US6515522B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 25, 2001 |
| Grant date | Feb 4, 2003 |
| Priority date | — |
| Expiry date | May 25, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2330/02
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A drive circuit capable of adjusting a capacitive load operation, for example, respective brightness of an electroluminescence (EL) element. The drive circuit is a constant current drive system and causes a plurality of capacitive loads, for example, EL elements, to emit light. This is done by setting a coil drive signal applied to the gate of a transistor Tr1. The transistor generates a surge pulse by intermittently connecting a direct current power source to a coil L1 of a step-up circuit 1. The coil drive signal is set to a frequency in accordance with an EL element as a capacitive load driven alone or a combination of EL elements simultaneously driven. Power generated by the step-up circuit 1 can be selected, brightness of a driven EL element E1 or E2 can individually be set or brightness of the EL elements E1 and E2 simultaneously driven can be set.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.