The LMT86-Q1 can be applied easily in the same way as other integrated-circuit temperature sensors. It can be glued or cemented to a surface.

To ensure good thermal conductivity, the backside of the LMT86-Q1 die is directly attached to the GND pin. The temperatures of the lands and traces to the other leads of the LMT86-Q1 will also affect the temperature reading.

Alternatively, the LMT86-Q1 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 IC, the LMT86-Q1 and accompanying wiring and circuits must be kept insulated and dry, to avoid leakage and corrosion. This is especially true if the circuit may operate at cold temperatures where condensation can occur. If moisture creates a short circuit from the output to ground or V_DD, the output from the LMT86-Q1 will not be correct. Printed-circuit coatings are often used to ensure that moisture cannot corrode the leads or circuit traces.

The thermal resistance junction to ambient (R_θJA or θ_JA) is the parameter used to calculate the rise of a device junction temperature due to its power dissipation. Use Equation 7 to calculate the rise in the LMT86-Q1 die temperature:

Equation 7.

where

• T_A is the ambient temperature,
• I_S is the supply current,
• I_Lis the load current on the output,
• and V_O is the output voltage.

For example, in an application where T_A = 30°C, V_DD = 5 V, I_S = 5.4 µA, V_O = 1777 mV junction temp 30.014°C self-heating error of 0.014°C. Because the junction temperature of the LMT86-Q1 is the actual temperature being measured, take care to minimize the load current that the LMT86-Q1 is required to drive. The Thermal Information table shows the thermal resistance of the LMT86-Q1.