This is one of the TTL types.
Part Number : 7805, KA7805
Package : TO-220, D-PAK
Function : 3-Terminal 1A, 5V, Positive Voltage Regulator
Manufactures : Fairchild Semiconductor
The KA78XX, KA78XXA series of three-terminal positive regulator are available in the TO-220/D-PAK package and 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 protection, making it essentially indestructible. If adequate heat sinking is provided, they can deliver over 1A output current. Although designed primarily as fixed voltage regulators, these devices can be used with external components to obtain adjustable voltages and currents.
Download Datasheet : [ 7805.PDF ]