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CD54HC157_08 Datasheet, PDF (6/15 Pages) Texas Instruments – High-Speed CMOS Logic Quad 2-Input Multiplexers
CD54/74HC157, CD54/74HCT157, CD54/74HC158, CD54/74HCT158
Test Circuits and Waveforms
tr = 6ns
INPUT
90%
50%
10%
tf = 6ns
VCC
GND
tTHL
INVERTING
OUTPUT
tPHL
tTLH
90%
50%
10%
tPLH
FIGURE 1. HC AND HCU TRANSITION TIMES AND PROPAGA-
TION DELAY TIMES, COMBINATION LOGIC
tr = 6ns
INPUT
tTHL
2.7V
1.3V
0.3V
INVERTING
OUTPUT
tPHL
tf = 6ns
3V
GND
tTLH
90%
1.3V
10%
tPLH
FIGURE 2. HCT TRANSITION TIMES AND PROPAGATION
DELAY TIMES, COMBINATION LOGIC
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