74HC_HCT238_Q100 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2013. All rights reserved.
Product data sheet Rev. 1 — 19 February 2013 10 of 17
NXP Semiconductors
74HC238-Q100; 74HCT238-Q100
3-to-8 line decoder/demultiplexer
Test data is given in Table 9.
Definitions for test circuit:
R
T
= Termination resistance should be equal to output impedance Z
o
of the pulse generator.
C
L
= Load capacitance including jig and probe capacitance.
R
L
= Load resistance.
S1 = Test selection switch
Fig 8. Load circuit for measuring switching times
V
M
V
M
t
W
t
W
10 %
90 %
0 V
V
I
V
I
negative
pulse
positive
pulse
0 V
V
M
V
M
90 %
10 %
t
f
t
r
t
r
t
f
001aad983
DUT
V
CC
V
CC
V
I
V
O
R
T
R
L
S1
C
L
open
G
Table 9. Test data
Type Input Load S1 position
V
I
t
r
, t
f
C
L
R
L
t
PHL
, t
PLH
74HC238-Q100 V
CC
6ns 15pF, 50 pF 1k open
74HCT238-Q100 3 V 6 ns 15 pF, 50 pF 1 k open
