Atmel ATmega128

320
2467S–AVR–07/09
ATmega128
Speed Grades Figure 152. Maximum frequency vs. V
CC
External Clock
Drive Waveforms
Figure 153. External Clock Drive Waveforms
External Clock
Drive
2.7V 4.5V 5.5V
Safe Operating Area
16 MHz
8 MHz
V
IL1
V
IH1
Table 131. External Clock Drive
Symbol Parameter
V
CC
= 2.7V to 5.5VV
CC
= 4.5V to 5.5V
UnitsMin Max Min Max
1/t
CLCL
Oscillator Frequency 0 8 0 16 MHz
t
CLCL
Clock Period 125 62.5 ns
t
CHCX
High Time 50 25 ns
t
CLCX
Low Time 50 25 ns
t
CLCH
Rise Time 1.6 0.5 μs
t
CHCL
Fall Time 1.6 0.5 μs
Δt
CLCL
Change in period from
one clock cycle to the
next
22%