Light-emitting element driving circuit and device using the same
US6078150A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 6, 1998 |
| Grant date | Jun 20, 2000 |
| Priority date | — |
| Expiry date | Mar 6, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/503
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A light-emitting element driving circuit includes a drive transistor having a first terminal receiving a power supply voltage, a second terminal coupled to an anode of a light-emitting element, and a control terminal receiving an input signal, the drive transistor supplying a pulse current and a first bias current to the light-emitting element. A constant-current source is coupled to the anode of the light-emitting element and supplies a second bias current to the light-emitting element. A compensation circuit controls the second bias current so that a variation in the first bias current due to a temperature variation can be compensated for thereby the sum of the first and second bias currents is kept constant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.