3.0 MOUNTING CONSIDERATIONS

The majority of the temperature that the LM56 is measuring

is the temperature of its leads. Therefore, when the LM56 is

placed on a printed circuit board, it is not sensing the tem-

perature of the ambient air. It is actually sensing the tem-

perature difference of the air and the lands and printed circuit

board that the leads are attached to. The most accurate

temperature sensing is obtained when the ambient tempera-

ture is equivalent to the LM56’s lead temperature.

As with any IC, the LM56 and accompanying wiring and

circuits must be kept insulated and dry, to avoid leakage and

corrosion. This is especially true if the circuit operates at cold

temperatures where condensation can occur. Printed-circuit

coatings are often used to ensure that moisture cannot

corrode the LM56 or its connections.

01289318

FIGURE 3. Simplified Schematic

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