Datasheet

652
8284D–AVR–6/11
ATmega169A/PA/329A/PA/3290A/PA/649A/P/6490A/P
are controlled by the Power Reduction Register. See ”PRR – Power Reduction Register” on
page 46 for details.
It is possible to calculate the typical current consumption based on the numbers from Table 30-
20 for other V
CC
and frequency settings than listed in Table 30-19.
30.10.3.1 Example 1
Calculate the expected current consumption in idle mode with USART0, TIMER1, and SPI
enabled at V
CC
= 3.0V and F = 1MHz. From Table 30-20, second column, we see that we need
to add 49.8% for the USART0, 48.6% for the SPI, and 46.3% for the TIMER1 module. Reading
from Figure 30-549, we find that the idle current consumption is ~0.13mA at V
CC
= 3.0V and
F = 1MHz. The total current consumption in idle mode with USART0, TIMER1, and SPI enabled,
gives:
Table 30-19. Additional Current Consumption for the different I/O modules (absolute values)
PRR bit Typical numbers
V
CC
= 2V, F = 1MHz V
CC
= 3V, F = 4MHz V
CC
= 5V, F = 8MHz
PRADC 23.75µA 212.1µA 938µA
PRUSART0 36.7µA 210.4µA 939µA
PRSPI 32.1µA 213µA 940µA
PRTIM1 24.2µA 217µA 940µA
PRLCD 27.3µA 208.8µA 935µA
Table 30-20. Additional Current Consumption (percentage) in Active and Idle mode
PRR bit
Additional Current consumption
compared to Active with external clock
(see Figure 30-548 and Figure 30-549)
Additional Current consumption
compared to Idle with external clock
(see Figure 30-553 and Figure 30-501)
PRADC 11.9% 45.7%
PRUSART0 13.2% 49.8%
PRSPI 12.8% 48.6%
PRTIM1 12.1% 46.3%
PRLCD 12.3% 46.7%
ICCtotal 0.13mA 1 0.498 0.486 0.463+++()• 0.45mA≈≈