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

capacitor from V

as 75

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

shown in Figure 5, are often useful.

01175408

FIGURE 4. LM45 with Decoupling from Capacitive Load

01175409

FIGURE 5. LM45 with R-C Damper

01175412

FIGURE 6. Temperature Sensor,

Single Supply, −20˚C to +100˚C

01175414

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

01175415

FIGURE 8. Fahrenheit Thermometer

01175416

FIGURE 9. Centigrade Thermometer (Analog Meter)

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