Datasheet for the LM45, an analog Celsius temperature sensor whose output voltage rises linearly with temperature, at about 10 mV per degree. The 185 KB PDF gives pinout, supply range, accuracy and application circuits. In fault finding it lets a technician measure the output pin and convert the reading to temperature, separating a bad sensor from a fault in the monitoring circuit. Small packages make markings hard to read, so confirm the part code against the document before swapping or substituting another sensor.
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