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Typical applications, Lm45 – Rainbow Electronics LM45 User Manual

Page 5

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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

IN

to ground and a series R-C damper such as

75

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

shown in

Figure 5, are often useful.

DS011754-8

FIGURE 4. LM45 with Decoupling from Capacitive Load

DS011754-9

FIGURE 5. LM45 with R-C Damper

DS011754-12

FIGURE 6. Temperature Sensor,

Single Supply, −20˚C to +100˚C

DS011754-14

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

DS011754-15

FIGURE 8. Fahrenheit Thermometer

DS011754-16

FIGURE 9. Centigrade Thermometer (Analog Meter)

LM45

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