1289318
FIGURE 3. Simplified Schematic
3.0 MOUNTING CONSIDERATIONS
As with any IC, the LM56 and accompanying wiring and cir-
cuits 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 cor-
rode the LM56 or its connections.
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 temper-
ature difference of the air and the lands and printed circuit
board that the leads are attached to. The most accurate tem-
perature sensing is obtained when the ambient temperature
is equivalent to the LM56's lead temperature.
9
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