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50
AT90S1200
0838H–AVR–03/02
External Clock Drive
Waveforms
Figure 37.
External Clock Drive
External Clock Drive
VIL1
VIH1
Table 23.
External Clock Drive
Symbol
Parameter
V
CC
= 2.7V to 4.0V
V
CC
= 4.0V to 6.0V
Units
Min
Max
Min
Max
1/t
CLCL
Oscillator Frequency
0
4.0
0
12.0
MHz
t
CLCL
Clock Period
250.0
83.3
ns
t
CHCX
High Time
100.0
33.3
ns
t
CLCX
Low Time
100.0
33.3
ns
t
CLCH
Rise Time
1.6
0.5
µs
t
CHCL
Fall Time
1.6
0.5
µs