Intel 8XC251SA - Manual (Page 32)

32
PRELIMINARY
8XC251SA/SB/SP/SQ HIGH-PERFORMANCE CHMOS MICROCONTROLLER
Figure 18. External Clock Drive Waveforms
Figure 19. AC Testing Input, Output Waveforms
Figure 20. Float Waveforms
0.7 V
CC
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0.45 V
V
CC
– 0.5
0.2 V
CC
– 0.1
T
CHCL
T
CLCX
T
CLCL
T
CLCH
T
CHCX
AC inputs during testing are driven at V
CC
– 0.5V for a logic 1
and 0.45 V for a logic 0. Timing measurements are made at
0.45 V
Inputs Outputs
A4118-01
V
IH MIN
V
OL MAX
V
CC
– 0.5
0.2 V
CC
+ 0.9
0.2 V
CC
– 0.1
a min of V
IH
for a logic 1 and V
OL
for a logic 0.
V
LOAD
+ 0.1 V
V
LOAD
– 0.1 V
Timing Reference
Points
V
LOAD
V
OH
– 0.1 V
V
OL
+ 0.1 V
For timing purposes, a port pin is no longer floating when a
100 mV change from load voltage occurs and begins to float
when a 100 mV change from the loading V
OH
/V
OL
level occurs
with I
OL/
I
OH
= ± 20 mA.
A4117-01