Die Junction Temperature
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Post Date:
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07/16/07
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Question:
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What is the measurement error on the die junction temperature if the supplied current differs from the one given for the diode characteristic specified in the data sheet?
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Answer:
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The diode characteristic given in the data sheet of e2v Broadband Data Conversion products is specified for a defined supplied current I0. If the user applies a different current, I1, then the error on the die junction temperature measurement will be as follows:
^V = (kT/q) ln(I1/ I0) where (kT/q) = 25.8mV at 27°C and 34.4 mV at 127°C. The error is a translation of the Vbe characteristic by ^V for a given temperature. |