Datasheet for the 78MXX family, the medium-current series of fixed positive three-terminal linear regulators rated around 500 mA. The 161 KB PDF lists output voltage options, dropout, line and load regulation, thermal limits and package pinouts. When diagnosing a dead supply section, it lets a technician confirm input, ground and output pins and the expected output for a given suffix such as 05 or 12. Pinouts differ between packages, so match the package type on the board before measuring or soldering a replacement.
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