74F269 查看數據表（PDF） - Philips Electronics
零件编号
产品描述 (功能)
比赛名单
74F269 Datasheet PDF : 14 Pages
| |||
Philips Semiconductors
8–bit bidirectional binary counter
Product specification
74F269
LOGIC SYMBOL
23 22 21 20 18 17 16 15
P0 P1 P2 P3 P4 P5 P6 P7
24
PE
1
U/D
12
CEP
13
CET
TC
14
11
CP
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
2 3 4 5 6 8 9 10
VCC=Pin 19
GND=Pin 7
SF00835
LOGIC SYMBOL (IEEE/IEC)
CTR DIV 256
24
M1[LOAD]
M2[COUNT]
1
M3[UP]
M4[DOWN]
12
&
13
G5
EN6
11
2, 3, 5, 6 +/C7
2, 4, 5, 6–
23
1, 7D [1]
22
[2]
21
[4]
20
[8]
18
[16]
17
[32]
16
[64]
15
[128]
3, 5, 6 CT=256
4, 5, 8 CT=0
2
3
4
5
6
8
9
10
14
SF00836
APPLICATION
CP
U/D
PE
P0 P1 P2 P3 P4 P5 P6 P7
PE
U/D
CP
CEP
TC
CET
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
P0 P1 P2 P3 P4 P5 P6 P7
PE
U/D
CP
CEP
TC
CET
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
P0 P1 P2 P3 P4 P5 P6 P7
PE
U/D
CP
CEP
TC
CET
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
P0 P1 P2 P3 P4 P5 P6 P7
PE
U/D
CP
CEP
TC
CET
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
Least significant 8-bit counter
Figure 1. Synchronous Multistage Counting Scheme
Most significant 8-bit counter
SF00851
MODE SELECT FUNCTION TABLE
INPUTS
CP
U/D
CEP
CET
PE
Pn
↑
X
X
X
l
l
↑
X
X
X
l
h
OUTPUTS
Qn
TC
L
(a)
H
(a)
OPERATING MODE
Parallel load
↑
h
l
l
h
X
Count Up
(a)
Count Up
↑
l
l
l
h
X
Count Down
(a)
Count Down
↑
X
h
l
h
X
↑
X
X
h
h
X
qn
(a)
Hold (do nothing)
qn
H
H = High voltage level
h = High voltage level one setup prior to the Low-to-High clock transition
L = Low voltage level
l = Low voltage level one setup time prior to the Low-to-High clock transition
q = Lower case letters indicate the state of the referenced output prior to the Low-to-High clock transition
X = Don’t care
↑ = Low-to-High clock transition
(a) = TC is Low when CET is Low and the counter is at Terminal Count. Terminal Count Up is with all Qn outputs High and Terminal Count
Down is with all Qn outputs Low.
1996 Jan 05
3
Share Link: 