Typical Applications

CAPACITIVE LOADS

Like most micropower circuits, the LM45 has a limited ability

to drive heavy capacitive loads. The LM45 by itself is able to

drive 500 pF without special precautions. If heavier loads are

anticipated, it is easy to isolate or decouple the load with a

resistor; see

Figure 4. Or you can improve the tolerance of

capacitance with a series R-C damper from output to

ground; see

Figure 5.

Any linear circuit connected to wires in a hostile environment

can have its performance affected adversely by intense elec-

tromagnetic sources such as relays, radio transmitters, mo-

tors with arcing brushes, SCR transients, etc, as its wiring

can act as a receiving antenna and its internal junctions can

act as rectifiers. For best results in such cases, a bypass ca-

pacitor from V

75

Ω in series with 0.2 or 1 µF from output to ground, as

shown in

Figure 5, are often useful.

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FIGURE 4. LM45 with Decoupling from Capacitive Load

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FIGURE 5. LM45 with R-C Damper

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FIGURE 6. Temperature Sensor,

Single Supply, −20˚C to +100˚C

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FIGURE 7. 4-to-20 mA Current Source (0˚C to +100˚C)

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FIGURE 8. Fahrenheit Thermometer

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FIGURE 9. Centigrade Thermometer (Analog Meter)

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