Motorola SN54LS641J, SN54LS642J, SN54LS645J, SN54LS640J, SN74LS645N Datasheet
...
CONNECTION DIAGRAMS DIP (TOP VIEW)
18 17 16 15 14 13
1 2 3 4 5 6
7
20 19
8
V
CC
DIR
B1 B2 B3 B5B4 B6
A1 A2 A3 A4 A5 A6 A7
9 10
A8 GND
12 11
B7 B8
18 17 16 15 14 13
1 2 3 4 5 6
7
20 19
8
V
CC
DIR
B1 B2 B3 B5B4 B6
A1 A2 A3 A4 A5 A6 A7
9 10
A8 GND
12 11
B7 B8
SN54/74LS640
SN54/74LS642
SN54/74LS641
SN54/74LS645
ENABLE
G
ENABLE
G
5-1
FAST AND LS TTL DATA
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 OUTPUT LOGIC
LS640 3-State Inverting
LS641 Open-Collector True
LS642 Open-Collector Inverting
LS645 3-State True
FUNCTION TABLE
CONTROL
OPERATION
INPUTS
G DIR
LS640
LS642
LS641
LS645
L L B data to A bus B data to A bus
L H A data to B bus A data to B bus
H X Isolation Isolation
H = HIGH Level, L = LOW Level, X = Irrelevant
SN54/74LS640
SN54/74LS641
SN54/74LS642
SN54/74LS645
OCTAL BUS TRANSCEIVERS
LOW POWER SCHOTTKY
ORDERING INFORMATION
SN54LSXXXJ Ceramic
SN74LSXXXN Plastic
SN74LSXXXDW SOIC
20
1
J SUFFIX
CERAMIC
CASE 732-03
20
1
N SUFFIX
PLASTIC
CASE 738-03
20
1
DW SUFFIX
SOIC
CASE 751D-03
5-2
FAST AND LS TTL DATA
SN54/74LS640 • SN54/74LS645
GUARANTEED OPERATING RANGES
Symbol Parameter Min Typ Max Unit
V
CC
Supply Voltage 54
74
4.5
4.75
5.0
5.0
5.5
5.25
V
T
A
Operating Ambient Temperature Range 54
74
–55
0
25
25
125
70
°C
54, 74 –3.0 mA
OH
54
74
–12
–15
mA
I
OL
Output Current — Low 54
74
12
24
mA
DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE (unless otherwise specified)
Limits
Symbol
Parameter
Min Typ Max
Unit
Test Conditions
V
IH
Input HIGH Voltage 2.0 V
Guaranteed Input HIGH Voltage for
All Inputs
54 0.5
VILInput LOW Voltage
74 0.6
V
Guaranteed Input LOW Voltage for
All Inputs
V
IK
Input Clamp Diode Voltage –0.65 –1.5 V VCC = MIN, IIN = –18 mA
54, 74 2.4 3.4 V VCC = MIN, IOH = 3.0 mA
VOHOutput HIGH Voltage
54, 74 2.0 V
VCC = MIN, IOH = MAX
54, 74 0.25 0.4 V IOL = 12 mA
VOLOutput LOW Voltage
74 0.35 0.5 V IOL = 24 mA
VIN = VIL or V
IH
per Truth Table
I
OZH
Output Off Current HIGH 20 µA VCC = MAX, V
OUT
= 2.7 V
I
OZL
Output Off Current LOW –400 µA VCC = MAX, V
OUT
= 0.4 V
A or B, DIR or G
20 µA VCC = MAX, VIN = 2.7 V
DIR or G
0.1 mA VCC = MAX, VIN = 7.0 V
IH
A or B
0.1 mA VCC = MAX, VIN = 5.5 V
I
IL
Input LOW Current –0.4 mA VCC = MAX, VIN = 0.4 V
I
OS
Output Short Circuit Current (Note 1) –40 –225 mA VCC = MAX
Power Supply Current
Total Output HIGH
70
I
CC
Total, Output LOW
90
mA
VCC = MAX
Total at HIGH Z
95
Note 1: Not more than one output should be shorted at a time, nor for more than 1 second.
AC CHARACTERISTICS (T
A
= 25°C, VCC = 5.0 V)
Limits
LS640 LS645
Symbol
Parameter
Min Typ Max Min Typ Max
Unit
Test Conditions
t
PLH
t
PHL
Propagation Delay
A to B
6.0
8.01015
8.01115
15
ns
t
PLH
t
PHL
Propagation Delay
B to A
6.0
8.01015
8.01115
15
ns
= 45 pF,
t
PZL
t
PZH
Output Enable Time
G
, DIR to A
312340
40
312640
40
ns
CL = 45 pF,
RL = 667 Ω
t
PZL
t
PZH
Output Enable Time
G
, DIR to B
312340
40
312640
40
ns
t
PLZ
t
PHZ
Output Disable Time
G
, DIR to A
151525
25
151525
25
ns
t
PLZ
t
PHZ
Output Disable Time
G
, DIR to B
151525
25
151525
25
ns
CL = 5.0 pF
I
OH
Output Current — High
Guaranteed Input LOW Voltage for
VCC = VCC MIN,
I
IH
Input HIGH Current
C
Loading...