Note 10: Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output due to heating effects can be

computed by multiplying the internal dissipation by the thermal resistance.

Note 11: For best long-term stability, any precision circuit will give best results if the unit is aged at a warm temperature, and/or temperature cycled for at least 46

hours before long-term life test begins. This is especially true when a small (Surface-Mount) part is wave-soldered; allow time for stress relaxation to occur. The

majority of the drift will occur in the first 1000 hours at elevated temperatures. The drift after 1000 hours will not continue at the first 1000 hour rate.

printed circuit board as shown in

Figure 2.

Thermal Resistance

Junction to Air

Thermal Time Constant

Thermal Response in

Still Air with Heat Sink

01268103

01268104

01268105

Thermal Response

in Stirred Oil Bath

with Heat Sink

Start-Up Voltage

vs. Temperature

Thermal Response in Still

Air without a Heat Sink

01268106

01268107

01268108

Quiescent Current

vs. Temperature

Accuracy vs Temperature

Noise Voltage

01268109

01268110

01268111

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