Datasheet for the 79LXX series, low-power fixed negative three-terminal regulators typically rated around 100 mA, supplied as a 157 KB PDF. The digits after 79L indicate the negative output voltage. It covers pinout, input range, regulation figures and package drawings for the small TO-92 and SO-8 style cases. Pin order differs from positive 78L parts, so it is worth checking before probing. Use it to confirm input, ground and output pins and the expected negative rail on a faulty analog supply.
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