How (not) to Fry a Thermometer

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If the thermometer is writing a zero to the master:

And if, due to noise on the data line, the voltage reaches the critical level:

Then a large amount of current can pass through the thermometer, possibly damaging it! Future tests will have to be done to discover if this is indeed the problem. If it is, there appears to be a solution: Put small resistors in series with the data line, and a Zener diode in parallel, to limit the current. Long-term tests should be able to demonstrate whether this protection actually works.