LM20EP micro SMD Light

Sensitivity

Exposing the LM20EP micro SMD package to bright sunlight

may cause the output reading of the LM20EP to drop by

1.5V. In a normal office environment of fluorescent lighting

the output voltage is minimally affected (less than a millivolt

drop). In either case it is recommended that the LM20EP

micro SMD be placed inside an enclosure of some type that

minimizes its light exposure. Most chassis provide more than

ample protection. The LM20EP does not sustain permanent

damage from light exposure. Removing the light source will

cause LM20EP’s output voltage to recover to the proper

value.

Applications Circuits

20099918

FIGURE 6. Centigrade Thermostat

20099919

FIGURE 7. Conserving Power Dissipation with Shutdown

20099928

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 LM20EP 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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