OCTAL BUS TRANSCEIVERS
These octal bus transceivers are designed for asynchronous two-way communication between data bus...
OCTAL BUS TRANSCEIVERS
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 transmission 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 device so that the buses are effectively isolated.
DEVICE LS640 LS641 LS642 LS645 OUTPUT 3-State Open-Collector Open-Collector 3-State LOGIC Inverting True Inverting True
SN54/74LS640 SN54/74LS641 SN54/74LS642 SN54/74LS645
OCTAL BUS TRANSCEIVERS
LOW POWER
SCHOTTKY
FUNCTION TABLE
CONTROL INPUTS G L L H DIR L H X LS640 LS642 B data to A bus A data to B bus Isolation OPERATION LS641 LS645 B data to A bus A data to B bus Isolation
20 1
J SUFFIX CERAMIC CASE 732-03
20 1
N SUFFIX PLASTIC CASE 738-03
H = HIGH Level, L = LOW Level, X = Irrelevant 20 1
DW SUFFIX SOIC CASE 751D-03
ORDERING INFORMATION
SN54LSXXXJ Ceramic SN74LSXXXN Plastic SN74LSXXXDW SOIC
CONNECTION DIAGRAMS DIP (TOP VIEW)
ENABLE VCC G B1 20 19 18 B2 17 B3 16 B4 15 B5 14 B6 13 B7 12 B8 11 ENABLE VCC G B1 20 19 18 B2 17 B3 16 B4 15 B5 14 B6 13 B7 12 B8 11
1 DIR
2 A1
3 A2
4 A3
5 A4
6 A5
7 A6
8 A7
9 A8
10 GND
1 DIR
2 A1
3 A2
4 A3
5 A4
6 A5
7 A6
8 A7
9 A8
10 GND
SN54 / 74LS640 SN54 / 74LS642
SN54 / 74LS641 SN54 / 74LS645
FAST AND LS TTL DATA 5-1
SN54/74LS640 SN54/74LS645
GUARANTEED OPERATING RANGES
Symbol VCC T...