74LCX157
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AC ELECTRICAL CHARACTERISTICS
1) Skew is defined as the absolute value of the difference between the actual propagation delay for any two outputs of the same device switch-
ing in the same direction, either HIGH or LOW (t
OSLH
= | t
PLHm
- t
PLHn
|, t
OSHL
= | t
PHLm
- t
PHLn
|)
2) Parameter guaranteed by design
CAPACITIVE CHARACTERISTICS
1) C
PD
is defined as the value of the IC’s internal equivalent capacitance which is calculated from the operating current consumption without
load. (Refer to Test Circuit). Average operating current can be obtained by the following equation. I
CC(opr)
= C
PD
x V
CC
x f
IN
+ I
CC
/4 (per
channel)
TEST CIRCUIT
C
L
= 50 pF or equivalent (includes jig and probe capacitance)
R
L
= 500Ω or equivalent
R
T
= Z
OUT
of pulse generator (typically 50Ω)
Symbol Parameter
Test Condition Value
Unit
V
CC
(V)
C
L
(pF)
R
L
(Ω)
t
s
= t
r
(ns)
-40 to 85 °C -55 to 125 °C
Min. Max. Min. Max.
t
PLH
t
PHL
Propagation Delay
Time A, B to Y
2.7
50 500 2.5
6.5 7.5
ns
3.0 to 3.6 1.5 6.0 6.9
t
PLH
t
PHL
Propagation Delay
Time SELECT to Y
2.7
50 500 2.5
8.0 9.2
ns
3.0 to 3.6 1.5 7.0 8.0
t
PLH
t
PHL
Propagation Delay
Time STROBE
to Y
2.7
50 500 2.5
8.0 9.2
ns
3.0 to 3.6 1.5 7.0 8.0
t
OSLH
t
OSHL
Output To Output
Skew Time (note1,
2)
3.0 to 3.6 50 500 2.5 1.0 1.0 ns
Symbol Parameter
Test Condition Value
Unit
V
CC
(V)
T
A
= 25 °C
Min. Typ. Max.
C
IN
Input Capacitance
3.3
V
IN
= 0 to V
CC
6pF
C
PD
Power Dissipation Capacitance
(note 1)
3.3 f
IN
= 10MHz
V
IN
= 0 or V
CC
25
pF
