74LCX138 Datasheet, PDF (5/12 Pages) Fairchild Semiconductor – Low Voltage 1-of-8 Decoder/Demultiplexer with 5V Tolerant Inputs

74LCX138
Table 8: AC Electrical Characteristics
Test Condition
Value
Symbol
Parameter
t_PLH t_PHL
t_PLH t_PHL
t_PLH t_PHL
t_OSLH
t_OSHL
Propagation Delay
Time A, B, C to Y
Propagation Delay
Time G1 to Y
Propagation Delay
Time G2 to Y
Output To Output
Skew Time (note1,
2)
V_CC
(V)
2.7
3.0 to 3.6
2.7
3.0 to 3.6
2.7
3.0 to 3.6
3.0 to 3.6
C_L R_L t_s = t_r
(pF) (Ω) (ns)
50 500 2.5
50 500 2.5
50 500 2.5
50 500 2.5
-40 to 85 °C
Min.
1.5
1.5
1.5
Max.
7.9
6.7
6.4
5.8
7.4
6.5
1.0
-55 to 125 °C
Min.
1.5
1.5
1.5
Max.
7.9
6.7
6.4
5.8
7.4
6.5
1.0
Unit
ns
ns
ns
ns
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
Test Condition
Value
Symbol
Parameter
V_CC
(V)
C_IN Input Capacitance
3.3
C_PD Power Dissipation Capacitance
3.3
(note 1)
V_IN = 0 to V_CC
f_IN = 10MHz
V_IN = 0 or V_CC
T_A = 25 °C
Unit
Min. Typ. Max.
6
pF
42
pF
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
Figure 4: Test Circuit
C_L = 50pF or equivalent (includes jig and probe capacitance)
R_L = 500Ω or equivalent
R_T = Z_OUT of pulse generator (typically 50Ω)
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