pass the power supply voltage, as shown in

Figure 4.Ina

noisy environment it may be necessary to add a capacitor

from the output to ground. A 1 µF output capacitor with the

4k

Ω output impedance will form a 40 Hz lowpass filter. Since

the thermal time constant of the LM50 is much slower than

the 25 ms time constant formed by the RC, the overall re-

sponse time of the LM50 will not be significantly affected. For

much larger capacitors this additional time lag will increase

the overall response time of the LM50.

3.0 Typical Applications

DS012030-17

*R2

≈ 2k with a typical 1300 ppm/˚C drift.

FIGURE 5. Block Diagram

DS012030-11

FIGURE 6. Centigrade Thermostat/Fan Controller

DS012030-13

FIGURE 7. Temperature To Digital Converter (Serial Output) (+125˚C Full Scale)

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