Temperature monitoring circuit for light-emitting diode

Abstract

The invention discloses a temperature monitoring circuit for a light-emitting diode. By means of the temperature monitoring circuit for the light-emitting diode, the temperature of any light-emitting diode in a light-emitting diode array can be monitored, and thus the instantaneity and accuracy of the monitoring of the temperature of the light-emitting diode can be improved. The monitoring circuit comprises a voltage difference obtaining circuit and a control circuit, wherein the input end of the voltage difference obtaining circuit is connected with the two ends of the light-emitting diode respectively, and the output end of the voltage difference obtaining circuit is connected with the input end of the control circuit. The voltage difference obtaining circuit is used for obtaining the voltage drop of the light-emitting diode, comparing the voltage drop with a preset reference voltage, obtaining a voltage difference value and outputting the voltage difference value to the control circuit. The control circuit is used for carrying out calculation to obtain the current temperature value of the light-emitting diode according to the voltage difference value and the temperature value corresponding to the reference voltage, and outputting the current temperature value of the light-emitting diode.

Description

technical field [0001] The invention relates to the field of electronic technology, in particular to a light-emitting diode temperature monitoring circuit used in a light-emitting diode array. Background technique [0002] In ultraviolet curing technology, ultraviolet curing lamps based on high-power ultraviolet light-emitting diode arrays have been more and more widely used as replacement products for traditional high-pressure mercury lamps. figure 1 and figure 2 An ultraviolet curing lamp composed of two ultraviolet light-emitting diode arrays is given. 11 and 21 are different types of high-power ultraviolet light-emitting diodes installed on the base plate respectively. The basic principle is to use high-power ultraviolet light-emitting diodes to form an array of light-emitting diodes, so as to obtain high-power ultraviolet output. Compared with high-pressure mercury lamps, UV curing lamps based on high-power ultraviolet light-emitting diode arrays have many advantage...

AI Technical Summary

Problems solved by technology

[0003] Generally speaking, the number of ultraviolet light-emitting diodes used in ultraviolet curing lamps based on high-power ultraviolet light-emitting diode arrays is relatively large. In order to increase the intensity of unit light power, the arrangement of ultraviolet light-emitting diodes is also relatively dense. Diodes are all high-power light-emitting diodes. The power of a single light-emitting diode is about 1W (watt) to 5W. It generates a lot of heat and rises rapidly. If the temperature of the light-emitting diode cannot be detected in time and dealt with accordingly, the life of the light-emitting diode may be reduced or even invalid.

[0004] At present, the commonly used method of embedding a temperature sensor is to indirectly obtain the temperature of the LED by detecting the temperature of the LED base plate. The real working temperature inside the diode chip has certain defects in the application fields such as high-power ultraviolet light-emitting diode arrays

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