74HC3G14 Datasheet, PDF (11/18 Pages) NXP Semiconductors – Inverting Schmitt-triggers

NXP Semiconductors
74HC3G14; 74HCT3G14
Triple inverting Schmitt trigger
14. Application information
The slow input rise and fall times cause additional power dissipation, which 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 (µW);
f_i = input frequency (MHz);
t_r = input rise time (ns); 10 % to 90 %;
t_f = input fall time (ns); 90 % to 10 %;
∆I_CC(AV) = average additional supply current (µA).
∆I_CC(AV) differs with positive or negative input transitions, as shown in Figure 12 and
Figure 13.
An example of a relaxation circuit using the 74HC3G14/74HCT3G14 is shown
in Figure 14.
200
∆I_CC(AV)
(µA)
150
100
mna036
positive-going
edge
50
0
0
2.0
linear change of V_I between 0.1V_CC to 0.9V_CC.
Fig 12. ∆I_CC(AV) as a function of V_CC for 74HC3G14
negative-going
edge
4.0
6.0
V_CC (V)
74HC_HCT3G14_3
Product data sheet
Rev. 03 — 8 May 2009
© NXP B.V. 2009. All rights reserved.
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