5.0 Applications Circuits

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FIGURE 6. Centigrade Thermostat

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FIGURE 7. Conserving Power Dissipation with Shutdown

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Most CMOS ADCs found in ASICs have a sampled data comparator input structure that is notorious for causing grief to analog

output devices such as the LM20 and many op amps. The cause of this grief is the requirement of instantaneous charge of the

input sampling capacitor in the ADC. This requirement is easily accommodated by the addition of a capacitor. Since not all ADCs

have identical input stages, the charge requirements will vary necessitating a different value of compensating capacitor. This ADC

is shown as an example only. If a digital output temperature is required please refer to devices such as the LM74.

FIGURE 8. Suggested Connection to a Sampling Analog to Digital Converter Input Stage

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