Datasheet for the LM7805, a fixed 5 V positive three-terminal linear regulator from the widely used 78xx family, provided as a 161 KB PDF. It lists pinout, input voltage range, output current, dropout, protection features and recommended input and output capacitors. A technician uses it to identify input, ground and output pins and confirm a steady 5 V output under load. Overheating or a missing output usually points to a shorted load or a failed regulator. Verify the package type before measuring or replacing.
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