2.0 Capacitive Loads
(Continued)
pass the power supply voltage, as shown in
Figure 4.
In a
noisy environment it may be necessary to add a capacitor
from the output to ground. A 1 µF output capacitor with the
4 kΩ 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.
DS012030-17
*R2
≈
2k with a typical 1300 ppm/˚C drift.
FIGURE 5. Block Diagram
3.0 Typical Applications
DS012030-11
FIGURE 6. Centigrade Thermostat/Fan Controller
DS012030-13
FIGURE 7. Temperature To Digital Converter (Serial Output) (+125˚C Full Scale)
5
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