LM56
Application Hints
(Continued)
01289318
FIGURE 3. Simplified Schematic
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.
9
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