
100
AT90S/LS4433
1042H–AVR–04/03
External Clock Drive
Waveforms
Figure 69. External Clock
Table 39. External Clock Drive
Symbol
Parameter
V
CC = 2.7V to 6.0V
V
CC = 4.0V to 6.0V
Units
Min
Max
Min
Max
1/t
CLCL
Oscillator Frequency
0.0
4.0
0.0
8.0
MHz
t
CLCL
Clock Period
250.0
125.0
ns
tCHCX
High Time
100.0
50.0
ns
t
CLCX
Low Time
100.0
50.0
ns
t
CLCH
Rise Time
1.6
0.5
s
tCHCL
Fall Time
1.6
0.5
s
VIL1
VIH1