LOGIC, BUS TRANSCVR OCTAL, 20DIP; Logic Device Type:Bidirectional; Supply Voltage Range:4.5V to 5.5V; Logic Case Style:DIP; No. of Pins:20; Operating Temperature Range:0°C to +70°C; SVHC:No SVHC (20-Jun-2011); Logic Function Number:74640; Logic IC Base Number:74640; Logic IC Family:ALS; Logic IC Function:Octal Bus Transceiver with 3-State Outputs; Package / Case:PDIP; Supply Voltage Max:5.5V; Supply Voltage Min:4.5V; Termination Type:Through Hole
These octal bus transceivers are designed for asynchronous two-way communication between data buses. These 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. The output-enable () input can be used to disable the device so that the buses are effectively isolated. The -1 version of the SN74ALS640B is identical to the standard version, except that the recommended maximum IOL for the -1 version is increased to 48 mA. There is no -1 version of the SN54ALS640B. The SN54ALS640B and SN54AS640 are characterized for operation over the full military temperature range of -55°C to 125°C. The SN74ALS640B and SN74AS640 are characterized for operation from 0°C to 70°C.