CD74HCT242 Datasheet, PDF (2/7 Pages) Texas Instruments – High Speed CMOS Logic Quad-Bus Transceiver with Three-State Outputs

CD74HCT242, CD74HC243, CD74HCT243
Functional Diagrams
CD74HCT242
CD74HC243, CD74HC243
3
A0
11
B0
3
A0
11
B0
4
A1
10
B1
4
A1
10
B1
5
A2
9
B2
5
A2
9
B2
6
A3
1
OEB
13
OEA
DIRECTION
SELECT LOGIC
8
B3
6
A3
1
OEB
13
OEA
DIRECTION
SELECT LOGIC
8
B3
TRUTH TABLE
HCT242 SERIES
HC, HCT243 SERIES
CONTROL INPUTS
DATA PORT STATUS
DATA PORT STATUS
OEB
OEA
An
Bn
An
Bn
H
H
O
I
O
I
L
H
Z
Z
Z
Z
H
L
Z
Z
Z
Z
L
L
I
O
I
O
NOTE:
H = High Voltage Level
L = Low Voltage Level
I = Input
O = Output (Same Level as Input)
O = Output (Inversion of Input Level)
Z = High Impedance
To prevent excess currents in the High Z modes all I/O terminals should be terminated with 10kΩ to 1MΩ resistors.
2