Datasheet for the 78XX series of fixed positive three-terminal linear voltage regulators, a 156 KB PDF. The two digits after 78 give the output voltage, such as 05 for 5 V or 12 for 12 V. The document covers pinout, input voltage range, dropout, output current, thermal shutdown and recommended capacitors. Technicians use it to identify input, ground and output pins and check whether a regulator delivers its rated voltage. Package pinouts vary, so confirm the case style on the board before probing or replacing.
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