This part is a kind of semiconductor called 74LS245.
Function of this product has TRI-STATE Octal Bus Transceiver.
Manufacturers : National Semiconductor
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Some of the text within the PDF file :
54LS245 DM54LS245 DM74LS245 TRI-STATE Octal Bus Transceiver June 1989 54LS245 DM54LS245 DM74LS245 TRI-STATE Octal Bus Transceiver General Description These octal bus transceivers are designed for asynchronous two-way communication between data buses The control function implementation minimizes external timing requirements The device allows data transmission from the A bus to the B bus or from the B bus to the A bus depending upon the logic level at the direction control (DIR) input The enable input (G) can be used to disable the device so that the buses are effectively isolated Y Y Y Y Y Y Features Y Y Y Bi-Directional bus transceiver in a high-density 20-pin package TRI-STATE outputs drive bus lines directly PNP inputs reduce DC loading on bus lines Hysteresis at bus inputs improv [ ... ]
74LS245 PDF Datasheet Download
