Typical Performance Characteristics (Continued)
Temperature Stability
Output Impedance
Minimum Operating
Current
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Ripple Rejection
Ripple Rejection
Ripple Rejection
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Line Transient Response
Load Transient Response
DS009060-44
DS009060-45
Application Hints
In operation, the LM138 develops a nominal 1.25V reference
voltage, VREF, between the output and adjustment terminal.
The reference voltage is impressed across program resistor
R1 and, since the voltage is constant, a constant current I1
then flows through the output set resistor R2, giving an out-
put voltage of
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