26.4 Maximum Speed vs. VCC
Maximum frequency is depending on VCC. As shown in Figure 26-2 , the Maximum Frequency
equals 8Mhz when VCC is contained between 2.7V and 4.5V and equals 16Mhz when VCC is
contained between 4.5V and 5.5V.
Figure 26-2. Maximum Frequency vs. VCC, AT90PWM2/2B/3/3B
16Mhz
8Mhz
Safe Operating Area
2.7V
4.5V
5.5V
26.5 PLL Characteristics
.
Table 26-3. PLL Characteristics - VCC = 2.7V to 5.5V (unless otherwise noted)
Symbol
PLLIF
Parameter
Min.
Typ.
1
Max.
Units
Input Frequency
PLL Factor
0.5
2
MHz
PLLF
64
PLLLT
Lock-in Time
64
µS
Note:
While connected to external clock or external oscillator, PLL Input Frequency must be selected to
provide outputs with frequency in accordance with driven parts of the circuit (CPU core, PSC...)
302
AT90PWM2/3/2B/3B
4317J–AVR–08/10
ATMEL [ ATMEL ]
