HD74HC4538
Switching Characteristics
(C
L
= 50 pF, Input t
r
= t
f
= 6 ns)
Item
Propagation delay
time
Symbol V
CC
(V)
t
PLH
2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
3.0
5.0
3.0
5.0
3.0
5.0
3.0
5.0
5.0
Ta = 25°C
Min
Typ Max
—
—
—
—
—
—
—
—
—
—
—
—
80
16
14
—
—
—
—
—
—
—
—
—
—
22
—
—
23
—
—
17
—
—
—
—
—
—
—
150
100
—
1.3
—
9
—
70
±0.1
235
47
40
260
52
44
235
47
40
235
47
40
—
—
—
—
—
—
—
—
—
—
—
—
Ta = –40 to +85°C
Min
Max
—
—
—
—
—
—
—
—
—
—
—
—
100
20
17
—
—
—
—
—
—
—
—
—
295
59
50
325
65
55
295
59
50
295
59
50
—
—
—
—
—
—
—
—
—
—
—
—
Unit
ns
Test Conditions
A or B to Q
t
PHL
ns
A or B to
Q
t
PHL
ns
C
D
to Q
t
PLH
ns
C
D
to
Q
Pulse width
t
w
ns
A, B, C
D
Output pulse width
t
WQ
ns
µs
µs
µs
%
R
X
= 1 kΩ, C
X
= 12 pF
R
X
= 10 kΩ, C
X
= 100 pF
R
X
= 10 kΩ, C
X
= 1000 pF
R
X
= 10 kΩ, C
X
= 10000 pF
R
X
= 10 kΩ, C
X
= 1000 pF
Pulse width match
between circuits in
the same package
∆t
WQ
Caution in use: In order to prevent any malfunctions due to noise, connect a high frequency performance capacitor
between V
CC
and GND, and keep the wiring between the External components and Cext, Rext/Cext pins
as short as possible.
Test Circuit
V
CC
Input A
Pulse Generator
Z
out
= 50
Ω
Input B
Pulse Generator
Z
out
= 50
Ω
Input Clear
Pulse Generator
Z
out
= 50
Ω
Cext Rext/Cext
Q
V
CC
Cext Rext
Output
See Function Table
C
L
=
50 pF
Output
Q
Clear
C
L
=
50 pF
Note : 1. C
L
includes probe and jig capacitance.
Rev.2.00 Mar 30, 2006 page 4 of 13
RENESAS [ RENESAS TECHNOLOGY CORP ]
