Function Select Table
Pin Descriptions
S2
S1
S0
Function
Parallel Load
Pin Names
Description
CP
Clock Pulse Input
L
L
L
L
L
H
L
CEP
Count Enable Parallel Input (Active LOW)
Serial Data Input/Count Enable
Trickle Input (Active LOW)
Select Inputs
Complement
Shift Left
Shift Right
Count Down
Clear
D0/CET
L
H
H
L
L
H
L
S0–S2
MR
H
H
H
H
Master Reset Input
L
H
L
P0–P3
D3
Preset Inputs
H
H
Count Up
Hold
Serial Data Input
H
TC
Terminal Count Output
Data Outputs
Q0–Q3
Q0–Q3
Complementary Data Outputs
Truth Table
Q
0 = LSB
Inputs
Outputs
MR S2 S1 S0 CEP D0/CET D3 CP Q3 Q2 Q1 Q0
TC
Mode
L
L
L
L
X
X
X
P3 P2 P1 P0
L
Preset (Parallel Load)
L
L
L
L
L
H
H
L
H
L
X
X
X
L
X
X
X
L
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Q3 Q2 Q1 Q0
D3 Q3 Q2 Q1
L
Invert
D3
Shift to LSB
L
L
H
L
Q2 Q1 Q0 D0 Q3 (Note 1) Shift to MSB
L
H
H
H
H
H
H
H
H
L
(Q0–3) minus 1
Q3 Q2 Q1 Q0
Q3 Q2 Q1 Q0
1
1
Count Down
L
L
L
H
X
X
L
L
X
X
Count Down with CEP not active
Count Down with CET not active
Clear
L
L
L
H
X
L
H
H
2
L
L
H
L
L
L
L
L
L
H
H
H
H
L
(Q0–3) plus 1
Q3 Q2 Q1 Q0
Q3 Q2 Q1 Q0
Q3 Q2 Q1 Q0
Count Up
L
L
H
X
X
X
X
X
X
X
X
X
X
X
L
X
X
X
X
X
X
X
X
X
X
X
X
2
Count Up with CEP not active
Count Up with CET not active
Hold
L
L
H
X
X
X
X
X
L
H
H
L
L
H
L
H
H
H
H
H
H
H
H
H
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
H
L
L
L
H
H
L
L
L
H
L
L
Asynchronous
Master Reset
H
H
H
H
H
L
L
L
H
X
X
X
H
H
H
H
L
H
L
H
H
H
1 = L if Q0–Q3 = LLLL
H if Q0–Q3 ≠ LLLL
2 = L if Q0–Q3 = HHHH
H if Q0–Q3 ≠ HHHH
H = HIGH Voltage Level
L = LOW Voltage Level
X = Don't Care
= LOW-to-HIGH Transition
Note 1: Before the clock, TC is Q3
After the clock, TC is Q2
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