Datasheet in PDF form for the ICL8069, a low-voltage bandgap voltage reference diode of about 1.2 V, historically made by Intersil. It covers pin identification, package outline, reference voltage tolerance, temperature coefficient and typical application circuits. A repair technician uses it to check that the reference in meters, ADC front ends or power supplies sits at the correct voltage, to pick the bias resistor for the right operating current, and to identify a suitable substitute when the original part has failed or drifted.
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