Philips Semiconductors
4-bit binary counters
Product specification
74F161A, 74F163A
74F163A MODE SELECT – FUNCTION TABLE
INPUTS
OUTPUTS
OPERATING MODE
SR
CP
CEP
CET
PE
Dn
Qn
TC
l
↑
X
X
X
X
L
L
Reset (clear)
h
↑
X
X
l
l
L
L
Parallel load
h
↑
X
X
l
h
H
(2)
h
↑
h
h
h
X
count
(2)
Count
h
h
H=
h=
L=
l=
qn =
X=
↑=
(1) =
(2) =
X
l
X
h
X
qn
(2)
Hold (do nothing)
X
X
l
h
X
qn
L
High voltage level
High voltage level one setup prior to the Low-to-High clock transition
Low voltage level
Low voltage level one setup prior to the Low-to-High clock transition
Lower case letters indicate the state of the referenced output prior to the Low-to-High clock transition
Don’t care
Low-to-High clock transition
The TC output is High when CET is High and the counter is at Terminal Count (HHHH for 74F161A)
The TC output is High when CET is High and the counter is at Terminal Count (HHHH for 74F163A)
74F161A LOGIC DIAGRAM
2
CP
1
MR
9
PE
10
CET
7
CEP
3
D0
D RQ
CP Q
4
D1
D RQ
CP Q
5
D2
D RQ
CP Q
6
D3
D RQ
CP Q
VCC = Pin 16
GND = Pin 8
1996 Jan 29
5
14
Q0
13
Q1
12
Q2
11
Q3
15
TC
SF00662