SNIS118I July 1999 – October 2025 LM50 , LM50HV
PRODUCTION DATA
The LM50 and LM50HV can be applied easily in the same way as other integrated-circuit temperature sensors. The device can be glued or cemented to a surface and the temperature is within about 0.2°C (for power supply up to 10V) of the surface temperature.
This presumes that the ambient air temperature is approximately the same as the surface temperature; if the air temperature are much higher or lower than the surface temperature, the actual temperature of the LM50 and LM50HV dies are at an intermediate temperature between the surface temperature and the air temperature.
To provide good thermal conductivity, the backside of the LM50 and LM50HV dies are directly attached to the GND pin. The lands and traces to the device is part of the printed-circuit board, which is the object whose temperature is being measured. These printed-circuit board lands and traces do not cause the LM50 and LM50HV temperature to deviate from the desired temperature.
Alternatively, the LM50 and LM50HV can be mounted inside a sealed-end metal tube, and can then be dipped into a bath or screwed into a threaded hole in a tank. As with any device, the LM50 and LM50HV and accompanying wiring and circuits must be kept insulated and dry, to avoid leakage and corrosion. This is especially true if the circuit can operate at cold temperatures where condensation can occur. Printed-circuit coatings and varnishes such as HUMISEAL® and epoxy paints or dips are often used to verify that moisture cannot corrode the device or the connections.