This part is a kind of semiconductor called KA7809AE.
Function of this product has 3-Terminal 1A Positive Voltage Regulator.
Manufacturers : Fairchild Semiconductor
Image and pinout :
Some of the text within the PDF file :
KA78XXE / KA78XXAE 3-Terminal 1 A Positive Voltage Regulator April 2015 KA78XXE / KA78XXAE 3-Terminal 1 A Positive Voltage Regulator Features • Output Current up to 1 A • Output Voltages of 5, 6, 8, 9, 10, 12, 15, 18, 24 V • Thermal Overload Protection • Short-Circuit Protection • Output Transistor Safe Operating Area Protection Description The KA78XXE / KA78XXAE series of three-terminal positive regulators is available in the TO-220 / D-PAK package with several fixed-output voltages, making them useful in a wide range of applications. Each type employs internal current limiting, thermal shut-down, and safe operating area. If adequate heat sinking is provided, they can deliver over 1 A output current. Although designed primarily as fixed-voltage regulators, these devices [ ... ]