This part is a kind of semiconductor called AN7809.

Function of this product has (AN78xx/F) 3-pin positive output voltage regulator (1 A type).

Manufacturers : Panasonic Semiconductor

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Voltage Regulators AN78xx/AN78xxF Series 3-pin positive output voltage regulator (1 A type) I Overview The AN78xx series and the AN78xxF series are 3pin, fixed positive output type monolithic voltage regulators. Stabilized fixed output voltage is obtained from unstable DC input voltage without using any external components. 11 types of fixed output voltage are available; 5V, 6V, 7V, 8V, 9V, 10V, 12V, 15V, 18V, 20V, and 24V. They can be used widely in power circuits with current capacity of up to 1A. AN78xx series (10.35) 10.0±0.3 φ3.7±0.1 Unit: mm 4.5±0.2 1.4±0.1 15.4±0.2 (4.5) 1.4 +0.15 –0.05 0.8 +0.15 –0.05 I Features • No external components • Output voltage: 5V, 6V, 7V, 8V, 9V, 10V, 12V, 15V, 18V, 20V, 24V • Built-in overcurrent limit circuit • Built-in thermal [ ... ]

AN7809 PDF Datasheet Download