SNVS774Q May 2004 – June 2020 LM117 , LM317-N
PRODUCTION DATA.
In Figure 31, the top regulator is +6 V above the bottom regulator. It is clear that when the input rises above +6 V plus the dropout voltage, only the top LM317-N regulates +6 V at the output. When the input falls below –6 V minus the dropout voltage, only the bottom LM317-N regulates –6 V at the output. For regions where the output is not clipped, there is no regulation taking place, so the output follows the input.