NXP Semiconductors
74HC14; 74HCT14
Hex inverting Schmitt trigger
1.5
I
CC
(mA)
1.2
mna849
I
CC
(mA)
1.8
mna850
1.5
1.2
0.9
0.9
0.6
0.6
0.3
0.3
0
0
1
2
3
4
V
I
(V)
5
0
0
1
2
3
4
5
V
I
(V)
6
a. V
CC
= 4.5 V
Fig 11. Typical 74HCT transfer characteristics
b. V
CC
= 5.5 V
15. Application information
The slow input rise and fall times cause additional power dissipation, this can be
calculated using the following formula:
P
add
= f
i
(t
r
I
CC(AV)
+ t
f
I
CC(AV)
)
V
CC
where:
P
add
= additional power dissipation (W);
f
i
= input frequency (MHz);
t
r
= rise time (ns); 10 % to 90 %;
t
f
= fall time (ns); 90 % to 10 %;
I
CC(AV)
= average additional supply current (A).
Average
I
CC(AV)
differs with positive or negative input transitions, as shown in
and
An example of a relaxation circuit using the 74HC14; 74HCT14 is shown in
74HC_HCT14
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© NXP B.V. 2012. All rights reserved.
Product data sheet
Rev. 6 — 19 September 2012
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