External Clock
Input
XTAL1
UT80CRH196KDS
Figure 9. External Clock Connections
VD D
TEST POINTS
0.0V
1.4V
1.4V
AC Testing inputs are driven at VDD for a Logic “1” and 0.0V for a Logic “0”. Timing measure-
ments are made at 1.4V.
Figure 10. AC Testing Input, Output Waveforms
VOH - 0.5V
VLOAD
VOL + 0.5V
TIMING REFERENCE
POINTS
VOH - 0.5V
VOL + 0.5V
For timing purposes a port pin is no longer floating when it changes to a voltage outside the ref-
erence points shown and begins to float when it changes to a voltage inside the reference points
shown. IOL = 4mA, IOH = -4mA.
Figure 11. Float Waveforms
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