
Application Information (Continued)
INVERTING REGULATOR SHUTDOWN METHODS
To use the ON /OFF pin in a standard buck configuration is
simple, pull it below 1.3V (@25C, referenced to ground) to
turn regulator ON, pull it above 1.3V to shut the regulator
OFF. With the inverting configuration, some level shifting is
required, because the ground pin of the regulator is no
longer at ground, but is now setting at the negative output
voltage level. Two different shutdown methods for inverting
regulators are shown in
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FIGURE 27. Inverting Regulator Ground Referenced Shutdown
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FIGURE 28. Inverting Regulator Ground Referenced Shutdown using Opto Device
LM2596
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