74HC138_12 Datasheet, PDF (8/19 Pages) NXP Semiconductors – 3-to-8 line decoder/demultiplexer; inverting

NXP Semiconductors
74HC138; 74HCT138
3-to-8 line decoder/demultiplexer; inverting
Table 7. Dynamic characteristics …continued
Voltages are referenced to GND (ground = 0 V); C_L = 50 pF unless otherwise specified; for test circuit see Figure 8.
Symbol Parameter Conditions
T_amb = 25 °C
T_amb = −40 °C
to +85 °C
T_amb = −40 °C Unit
to +125 °C
Min Typ Max Min
Max
Min
Max
For type 74HCT138
t_pd
propagation An to Yn; see Figure 6
[1]
delay
V_CC = 4.5 V
-
20 35
-
44
-
53 ns
V_CC = 5 V; C_L = 15 pF
-
17 -
-
-
-
-
ns
E3 to Yn; see Figure 6
[1]
V_CC = 4.5 V
-
18 40
-
50
-
60 ns
V_CC = 5 V; C_L = 15 pF
-
19 -
-
-
-
-
ns
En to Yn; see Figure 7
[1]
V_CC = 4.5 V
-
19 40
-
50
-
60 ns
V_CC = 5 V; C_L = 15 pF
-
19 -
-
-
-
-
ns
t_t
transition Yn; see Figure 6 and
[2]
time
Figure 7
V_CC = 4.5 V
-
7 15
-
19
-
22 ns
C_PD
power
C_L = 50 pF; f = 1 MHz;
[3] _-
67 -
-
-
-
-
pF
dissipation V_I = GND to V_CC
capacitance
[1] t_pd is the same as t_PLH and t_PHL.
[2] t_t is the same as t_THL and t_TLH.
[3] C_PD is used to determine the dynamic power dissipation (P_D in μW).
P_D = C_PD × V_CC2 × f_i × N + (C_L × V_CC2 × f_o) where:
f_i = input frequency in MHz;
f_o = output frequency in MHz;
C_L = output load capacitance in pF;
V_CC = supply voltage in V;
N = number of inputs switching;
(C_L × V_CC2 × f_o) = sum of outputs.
74HC_HCT138
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 4 — 27 June 2012
© NXP B.V. 2012. All rights reserved.
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