datasheets 74ls640 free download

File name 74ls640.pdf

SN54/74LS640 SN54/74LS641 OCTAL BUS TRANSCEIVERS SN54/74LS642 SN54/74LS645 These octal bus transceivers are designed for asynchronous two-way communication between data buses. Control function implementation minimizes external timing requirements. These circuits allow data transmis- sion from the A bus to B or from the B bus to A bus depending upon the logic level of the direction control (DIR) input. Enable input (G) can disable the OCTAL BUS TRANSCEIVERS device so that the buses are effectively isolated. LOW POWER SCHOTTKY DEVICE OUTPUT LOGIC LS640 3-State Inverting LS641 Open-Collector True LS642 Open-Collector Inverting LS645 3-State True J SUFFIX CERAMIC FUNCTION TABLE CASE 732-03 20 CONTROL OPERATION 1 INPUTS LS640 LS641 G DIR LS642 LS645 N SUFFIX PLASTIC L L B data to A bus B data to A bus CASE 738-03 20 L H A data to B bus A data to B bus 1 H X