74LS245 Octal Bus Transceiver Tri-State


The 74LS series of integrated circuits (ICs) was one of the most popular logic families of transistor-transistor logic (TTL) logic chips. 74LS series is a bipolar, low-power Schottky IC. 74LS245 octal bus transceiver is designed for asynchronous two-way communication between data buses. The control function implementation minimizes external timing requirements.

74LS245 Features

  • Tri-State Outputs Drive Bus Lines Directly
  • PNP Inputs Reduce DC Loading on Bus Lines
  • Hysteresis Inputs
  • Designed for use as Bus Oriented Transmitters/Receivers
  • Standard TTL Switching Voltages

74LS245 Specifications

Supply Voltage4.75 – 5.25Vdc
Maximum Clock Frequency40Mhz
Power Dissipation2mW/gate @100kHz
Minimum Output Current8mA
Propagation Delay10nS
Fan Out (TTL Loads)20

74LS245 Pinout Diagram

74LS245 Pin Description

Pin NoPin NameDescription
1DIRControls signal direction; Low = Bx to Ax, High = Ax to Bx
2A1Channel 1, (A) side
3A2Channel 2, (A) side
4A3Channel 3 Of Transceiver (A)
5A4Channel 4 Of Transceiver (A)
6A5Channel 5 Of Transceiver (A)
7A6Channel 6 Of Transceiver (A)
8A7Channel 7 Of Transceiver (A)
9A8Channel 8 Of Transceiver (A)
11B8Channel 8 Of Transceiver (B)
12B7Channel 7 Of Transceiver (B)
13B6Channel 6 Of Transceiver (B)
14B5Channel 5 Of Transceiver (B)
15B4Channel 4 Of Transceiver (B)
16B3Channel 3 Of Transceiver (B)
17B2Channel 2 Of Transceiver (B)
18B1Channel 1 Of Transceiver (B)
19OE’Enable Output Active Low
20VCCPositive Supply


  • Transmit the data in the form of voice or data or video over the wireless medium.

74LS245 Alternative Equivalent


Download 74LS245 Octal Bus Transceiver Tri-State Datasheet from the link given below.