EP 0952757 A3 20010307 - Circuit for controlling the light intensity of current controlled LEDS for display illumination
Title (en)
Circuit for controlling the light intensity of current controlled LEDS for display illumination
Title (de)
Schaltungsanordnung zur Einstellung der Helligkeit stromgesteurter Leuchtdioden zur Beleuchtung einer Anzeige
Title (fr)
Circuit de commande de l'intensité lumineuse de diodes électroluminescentes controlées en courant pour l'éclairage d'afficheurs
Publication
Application
Priority
DE 19818621 A 19980425
Abstract (en)
[origin: EP0952757A2] The circuit has a control unit (2) that receives (6) a signal corresponding to the desired intensity and sets the LED (1) control current taking into account a degradation value. The control unit determines the degradation value by recording the operating duration of the diode and places a corresponding value in a memory (7) containing degradation information. The control unit determines the degradation value from the stored information and the measured operating duration and updates it at appropriate time intervals.
IPC 1-7
IPC 8 full level
H05B 33/08 (2006.01); H05B 37/03 (2006.01); H05B 44/00 (2022.01)
CPC (source: EP US)
H05B 45/10 (2020.01 - EP US); H05B 45/58 (2020.01 - EP US); H05B 47/20 (2020.01 - EP US); H05B 47/28 (2020.01 - EP US)
Citation (search report)
- [YD] DE 19602891 A1 19970807 - KAMMERER GMBH M [DE]
- [Y] WO 9205608 A1 19920402 - FINISAR CORP [US]
- [A] EP 0583186 A1 19940216 - FRANCE TELECOM [FR]
- [A] EP 0702347 A1 19960320 - TOSHIBA KK [JP]
- [A] EP 0669684 A2 19950830 - FUJITSU LTD [JP]
- [A] US 5719675 A 19980217 - KILLPATRICK JOSEPH E [US], et al
- [A] EP 0497431 A1 19920805 - SHARP KK [JP]
- [A] DE 19540326 A1 19970430 - BOSCH GMBH ROBERT [DE]
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
DOCDB simple family (publication)
EP 0952757 A2 19991027; EP 0952757 A3 20010307; EP 0952757 B1 20040804; DE 19818621 A1 19991028; DE 59910096 D1 20040909
DOCDB simple family (application)
EP 99107236 A 19990414; DE 19818621 A 19980425; DE 59910096 T 19990414