Patent · US Expired

Drive circuit for an LED array

US6864867B2 · kind B2 · utility

44Cited by
12References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 12, 2002
Grant dateMar 8, 2005
Priority date
Expiry dateDec 15, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05B45/46
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A drive circuit for an LED array comprises a first LED cluster and at least one second LED cluster. A control loop is designed to drive a switch of the first LED cluster so as to achieve a constant mean value of the current (ILED) flowing through the first LED cluster the control loop being designed for also driving switches of the further LED clusters. The drive circuit also comprises a total current detection device (RMES) with the aid of which it is possible to determine an actual magnitude (UMess) which corresponds to the sum of the currents through at least two of the second LED cluster. A comparison unit compares the actual magnitude (UMess) with a predefinable desired magnitude (UOL)

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.