Nexperia
74HC688
8-bit magnitude comparator
10.1 Waveforms and test circuit
aaa-028706
P=Q output
V
OH
V
OL
t
PLH
t
THL
t
TLH
V
X
V
Y
V
Y
V
X
t
PHL
V
M
V
M
Pn, Qn input
V
I
GND
V
M
V
M
Measurement points are given in Table 8.
V
OL
and V
OH
are typical voltage output levels that occur with the output load.
Figure 6. Waveforms showing the word inputs (Pn, Qn) to the equal to output (P=Q) propagation delays and the
output transition times.
aaa-028705
E input
V
I
GND
P=Q output
V
OH
V
OL
t
PLH
t
THL
t
TLH
V
X
V
Y
V
Y
V
X
t
PHL
V
M
V
M
V
M
V
M
Measurement points are given in Table 8.
V
OL
and V
OH
are typical voltage output levels that occur with the output load.
Figure 7. Waveforms showing the enable input (E) to the equal to output (P=Q) propagation delays and the output
transition times.
Table 8. Measurement points
Input Output
V
I
V
M
V
M
V
X
V
Y
GND to V
CC
0.5V
CC
0.5V
CC
0.1V
CC
0.9V
CC
74HC688 All information provided in this document is subject to legal disclaimers. © Nexperia B.V. 2018. All rights reserved.
Product data sheet Rev. 3 — 4 July 2018
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