74LCX257
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Table 7: Dynamic Switching Characteristics
1) Number of outputs defined as "n". Measured with "n-1" outputs switching from HIGH to LOW or LOW to HIGH. The remaining output is
measured in the LOW state.
Table 8: 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
Table 9: 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)
Symbol Parameter
Test Condition Value
Unit
V
CC
(V)
T
A
= 25 °C
Min. Typ. Max.
V
OLP
Dynamic Low Level Quiet
Output (note 1)
3.3
C
L
= 50pF
V
IL
= 0V, V
IH
= 3.3V
0.8
V
V
OLV
-0.8
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
1.5 6.5 1.5 6.5
ns
3.0 to 3.6 1.5 6.0 1.5 6.0
t
PLH
t
PHL
Propagation Delay
Time (SELECT to Y)
2.7
50 500 2.5
1.5 8.5 1.5 8.5
ns
3.0 to 3.6 1.5 7.0 1.5 7.0
t
PZL
t
PZH
Output Enable Time 2.7
50 500 2.5
1.5 8.5 1.5 8.5
ns
3.0 to 3.6 1.5 7.0 1.5 7.0
t
PLZ
t
PHZ
Output Disable Time 2.7
50 500 2.5
1.5 6.0 1.5 6.0
ns
3.0 to 3.6 1.5 5.5 1.5 5.5
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
7pF
C
OUT
Output Capacitance
3.3
V
IN
= 0 to V
CC
8pF
C
PD
Power Dissipation Capacitance
(note 1)
3.3 f
IN
= 10MHz
V
IN
= 0 or V
CC
25
pF
