Rainbow Electronics T89C51CC02 - Manual (Page 135)

Rev.A - May 17, 2001 135
Preliminary
T89C51CC02
19.4.5. External Clock Drive Waveforms
19.4.6. AC Testing Input/Output Waveforms
AC inputs during testing are driven at V
CC
- 0.5 for a logic “1” and 0.45V for a logic “0”. Timing measurement
are made at V
IH
min for a logic “1” and V
IL
max for a logic “0”.
19.4.7. Float Waveforms
For timing purposes as 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 loaded V
OH
/V
OL
level occurs. I
OL
/I
OH
≥ ±
20mA.
V
CC
-0.5V
0.45V
0.7V
CC
0.2V
CC
-0.1
T
CHCL
T
CLCX
T
CLCL
T
CLCH
T
CHCX
INPUT/OUTPUT
0.2 V
CC
+ 0.9
0.2 V
CC
- 0.1
V
CC
-0.5 V
0.45 V
FLOAT
V
OH
- 0.1 V
V
OL
+ 0.1 V
V
LOAD
V
LOAD
+ 0.1 V
V
LOAD
- 0.1 V