74LS645 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. 74LS645 octal bus transceivers are designed for asynchronous two-way communication between data buses. The devices transmit data from the A bus to the B bus or from the B bus to the A bus depending upon the level at the direction control (DIR) input.

74LS645 Features

• Designed for Asynchronous two-way Communication between Data Buses
• Hysteresis at Bus Inputs Improves Noise Margins
• 3-State Outputs Drive Bus Lines Directly
• Operating Temperature up to 70°C
• Standard TTL Switching Voltages

74LS645 Specifications

Supply Voltage	4.75 – 5.25Vdc
Maximum Clock Frequency	40Mhz
Power Dissipation	2mW/gate @100kHz
Minimum Output Current	8mA
Propagation Delay	10nS
Fan Out (TTL Loads)	20

74LS645 Pinout Diagram

74LS645 Pin Description

Pin No	Pin Name	Description
1	DIR	Direction Control Pin
2	A1	Input/Output of Bus Transceiver A
3	A2	Input/Output of Bus Transceiver A
4	A3	Input/Output of Bus Transceiver A
5	A4	Input/Output of Bus Transceiver A
6	A5	Input/Output of Bus Transceiver A
7	A6	Input/Output of Bus Transceiver A
8	A7	Input/Output of Bus Transceiver A
9	A8	Input/Output of Bus Transceiver A
10	GND	Ground
11	B8	Input/Output of Bus Transceiver B
12	B7	Input/Output of Bus Transceiver B
13	B6	Input/Output of Bus Transceiver B
14	B5	Input/Output of Bus Transceiver B
15	B4	Input/Output of Bus Transceiver B
16	B3	Input/Output of Bus Transceiver B
17	B2	Input/Output of Bus Transceiver B
18	B1	Input/Output of Bus Transceiver B
19	G’	Enable Pin
20	VCC	Positive Supply

Applications

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

74LS645 Alternative Equivalent

74LS640

Download 74LS645 Octal Bus Transceiver Tri-State Datasheet from the link given below.