CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of
the device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
NOTE:
4.
θ
JA
is measured with the component mounted on an evaluation PC board in free air.
DC Electrical Specifications
TEST
CONDITIONS
PARAMETER
HC TYPES
High Level Input
Voltage
V
IH
-
-
2
4.5
6
Low Level Input
Voltage
V
IL
-
-
2
4.5
6
High Level Output
Voltage
CMOS Loads
High Level Output
Voltage
TTL Loads
Low Level Output
Voltage
CMOS Loads
Low Level Output
Voltage
TTL Loads
Input Leakage
Current
Quiescent Device
Current
Three-State Leakage
Current
I
I
I
CC
I
OZ
V
CC
or
GND
V
CC
or
GND
V
IL
or V
IH
V
OL
V
IH
or V
IL
V
OH
V
IH
or V
IL
-0.02
-0.02
-0.02
-
-6
-7.8
0.02
0.02
0.02
-
6
7.8
-
0
V
O
=
V
CC
or
GND
2
4.5
6
-
4.5
6
2
4.5
6
-
4.5
6
6
6
6
1.5
3.15
4.2
-
-
-
1.9
4.4
5.9
-
3.98
5.48
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
0.5
1.35
1.8
-
-
-
-
-
-
0.1
0.1
0.1
-
0.26
0.26
±0.1
8
±0.5
1.5
3.15
4.2
-
-
-
1.9
4.4
5.9
-
3.84
5.34
-
-
-
-
-
-
-
-
-
-
-
-
0.5
1.35
1.8
-
-
-
-
-
-
0.1
0.1
0.1
-
0.33
0.33
±1
80
±5
1.5
3.15
4.2
-
-
-
1.9
4.4
5.9
-
3.7
5.2
-
-
-
-
-
-
-
-
-
-
-
-
0.5
1.35
1.8
-
-
-
-
-
-
0.1
0.1
0.1
-
0.4
0.4
±1
160
±10
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
µA
µA
µA
SYMBOL
V
I
(V)
I
O
(mA)
V
CC
(V)
25
o
C
MIN
TYP
MAX
-40
o
C TO 85
o
C -55
o
C TO 125
o
C
MIN
MAX
MIN
MAX
UNITS
3
CD74HC646, CD74HC648
Prerequisite for Switching Specifications
25
o
C
PARAMETER
HC TYPES
Maximum Frequency
f
MAX
2
4.5
6
Setup Time Data to Clock
t
SU
2
4.5
6
Hold Time Data to Clock
t
H
2
4.5
6
Clock Pulse Width
t
W
2
4.5
6
6
30
35
60
12
10
35
7
6
80
16
14
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
5
25
29
75
15
13
45
9
8
100
20
17
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
4
20
23
90
18
15
55
11
9
120
24
20
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
MHz
MHz
MHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
SYMBOL
V
CC
(V)
MIN
TYP
MAX
-40
o
C TO 85
o
C
MIN
TYP
MAX
-55
o
C TO 125
o
C
MIN
TYP
MAX
UNITS
Switching Specifications
C
L
= 50pF, Input t
r
, t
f
= 6ns
25
o
C
-40
o
C TO
85
o
C
MAX
MIN
MAX
-55
o
C TO
125
o
C
MIN
MAX
UNITS
PARAMETER
HC TYPES
Propagation Delay
Store A Data to B Bus
Store B Data to B Bus (646)
SYMBOL
TEST
CONDITIONS
V
CC
(V)
MIN
TYP
t
PHL
, t
PLH
C
L
= 50pF
2
4.5
C
L
= 15pF
C
L
= 50pF
5
6
2
4.5
C
L
= 15pF
C
L
= 50pF
5
6
2
4.5
C
L
= 15pF
C
L
= 50pF
5
6
-
-
-
-
-
-
-
-
-
-
-
-
-
-
18
-
-
-
20
-
-
-
12
-
220
44
-
37
240
48
-
41
135
27
-
23
-
-
-
-
-
-
-
-
-
-
-
-
275
55
-
47
300
60
-
51
170
34
-
29
-
-
-
-
-
-
-
-
-
-
-
-
330
66
-
56
360
72
-
61
205
41
-
35
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
t
PHL,
t
PLH
Store A Data to B Bus
Store B Data to B Bus (648)
C
L
= 50pF
A Data to B Bus
B Data to A Bus (646)
t
PLH,
t
PHL
C
L
= 50pF
4
CD74HC646, CD74HC648
Switching Specifications
C
L
= 50pF, Input t
r
, t
f
= 6ns
(Continued)
25
o
C
PARAMETER
A Data to B Bus
B Data to A Bus (648)
SYMBOL
t
PLH
, t
PHL
TEST
CONDITIONS
C
L
= 50pF
V
CC
(V)
2
4.5
C
L
= 15pF
C
L
= 50pF
Select to Data (646)
t
PLH
, t
PHL
C
L
= 50pF
5
6
2
4.5
C
L
= 15pF
C
L
= 50pF
Select to Data (648)
t
PLH
, t
PHL
C
L
= 50pF
5
6
2
4.5
C
L
= 15pF
C
L
= 50pF
Three-State Disabling Time
Bus to Output or Register to
Output
t
PLZ
, t
PHZ
C
L
= 50pF
5
6
2
4.5
C
L
= 15pF
C
L
= 50pF
Three-State Enabling Time
Bus to Output or Register to
Output
t
PZL
, t
PZH
C
L
= 50pF
5
6
2
4.5
C
L
= 15pF
C
L
= 50pF
Output Transition Time
t
TLH
, t
THL
C
L
= 50pF
5
6
2
4.5
C
L
= 50pF
Input Capacitance
Three-State Output
Capacitance
Maximum Frequency
Power Dissipation Capacitance
(Notes 5, 6)
NOTES:
5. C
PD
is used to determine the dynamic power consumption, per package.
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