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About Temperature Observation

Temperature observation is possibility to define LED p-n junction temperature and observe temperature

changing using current-voltage dependence. Driver generates low current signals with amplitude 12 mA

and duration 500 ns for plugged LED. These signals are placed between driving signals and don’t affect

LED temperature. Special block of PCB-driver-51 registers the pulse voltage value and converts it into

constant voltage. Since there is a univocal dependence of voltage on intrinsic LED temperature, it

becomes possible to judge temperature changing by observing voltage changing.

Family of current-voltage characteristics at different temperatures

Voltage-temperature dependence at 12mA measuring signal. Straight-line relationship is clearly seen

Every LED has a unique current-voltage characteristic, that’s why relation between output voltage and

temperature will be different depending on measured LED. Therefore, for measuring exact p-n junction

temperature, the calibration for every LED is needed. To calibrate we recommend measuring voltage

values at room temperature and some other temperature and use linear approximation (U(T)=kT+b).

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The above specifications are for reference purpose only and subjected to change without prior notice