Datasheet for the 79XX family of fixed negative three-terminal linear regulators, a 167 KB PDF. The last two digits give the negative output voltage, for example 05 for minus 5 V. Contents include pinout, input range, current capability, protection and recommended capacitors. The pin order is not the same as the positive 78XX series, a frequent source of mistakes when replacing parts. Use it to identify input, ground and output pins and to confirm the negative rail on a dual-supply board.
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