The ON/OFF pin is floating or the diode is connected backwards. Fix:
Open Schematic Capture, press P , and search for "LM2596". 3. Simulation & Circuit Design proteus lm2596 library
Once your basic LM2596 library is working, push further: The ON/OFF pin is floating or the diode
: Many libraries include the exact footprint (like TO-220 or TO-263) needed to transition from a digital simulation to a physical PCB layout. proteus lm2596 library
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