Patent · US Active

System and method for estimating the junction temperature of a light emitting diode

US8534914B2 · kind B2 · utility

1Cited by

3References

14Claims

0Family size

Assignee

NXP B.V. · NL

Inventors

Viet Nguyen Hoang · Leuven, BE
Radu Surdeanu · Roosbeek, BE
Pascal Bancken · Opwijk, BE
Benoit Bataillou · Evergem, BE
David Van Steenwinckel · Holsbeek, BE

Key dates

Filing date	Jan 27, 2009
Grant date	Sep 17, 2013
Priority date	—
Expiry date	Aug 16, 2030

Classification

Technology area (CPC H)Electricity
CPC primaryH05B45/56
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

A method of estimating the junction temperature of a light emitting diode comprises driving a forward bias current through the diode, the current comprising a square wave which toggles between high and low current values (Ihigh, llow), the high current value (lhigh) comprising an LED operation current, and the low current value (ILOW) comprising a non-zero measurement current. The forward bias voltage drop (Vf) is sampled and the forward bias voltage drop (Vflow) is determined at the measurement current (ILOW)—The temperature is derived from the determined forward bias voltage drop.

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