circuit board as shown in Figure 2. (Continued)

1.0 Mounting

The LM60 can be applied easily in the same way as other

integrated-circuit temperature sensors. It can be glued or

cemented to a surface. The temperature that the LM60 is

sensing will be within about +0.1˚C of the surface tempera-

ture that LM60’s leads are attached to.

This presumes that the ambient air temperature is almost the

same as the surface temperature; if the air temperature were

much higher or lower than the surface temperature, the

actual temperature of the LM60 die would be at an interme-

diate temperature between the surface temperature and the

air temperature.

To ensure good thermal conductivity the backside of the

LM60 die is directly attached to the GND pin. The lands and

traces to the LM60 will, of course, be part of the printed

circuit board, which is the object whose temperature is being

measured. These printed circuit board lands and traces will

not cause the LM60’s temperature to deviate from the de-

sired temperature.

Alternatively, the LM60 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 LM60 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 conden-

sation can occur. Printed-circuit coatings and varnishes such

as Humiseal and epoxy paints or dips are often used to

ensure that moisture cannot corrode the LM60 or its connec-

tions.

The thermal resistance junction to ambient (

θ

parameter used to calculate the rise of a device junction

temperature due to the device power dissipation. For the

LM60 the equation used to calculate the rise in the die

temperature is as follows:

T

θ

where I

the output.

The table shown in Figure 3 summarizes the rise in die

temperature of the LM60 without any loading, and the ther-

mal resistance for different conditions.

01268114

FIGURE 2. Printed Circuit Board Used

for Heat Sink to Generate All Curves.

1

with 2 oz. Copper Foil or Similar.

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