74LS240 Octal Inverter Line Driver 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. 74LS240 buffers/line drivers are designed to improve both the performance and PC board density of 3-STATE buffers/ drivers employed as memory address drivers, clock drivers, and bus-oriented transmitters/receivers

74LS240 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

74LS240 Specifications

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

74LS240 Pinout Diagram

74LS240 Pin Description

Pin NoPin NameDescription
11G’Channel 1 output enable
21A1Channel 1, (A) side 1
32Y4Channel 2, Y side 4
41A2Channel 1, (A) side 2
52Y3Channel 2, Y side 3
61A3Channel 1, (A) side 3
72Y2Channel 2, Y side 2
81A4Channel 1, (A) side 4
92Y1Channel 2, Y side 1
112A1Channel 2, (A) side 1
121Y4Channel 1, Y side 4
132A2Channel 2, (A) side 2
141Y3Channel 1, Y side 3
152A3Channel 2, (A) side 3
161Y2Channel 1, Y side 2
172A4Channel 2, (A) side 4
181Y1Channel 1, Y side 1
192G’Channel 2 output enable
20VCCPositive Supply


  • Communicate digital signals across circuit-board traces and cables

74LS240 Alternative Equivalent

74LS241, 74LS245

Download 74LS240 Octal Inverter Line Driver Tri-State Datasheet from the link given below.