Datasheet

391
2549O–AVR–05/12
ATmega640/1280/1281/2560/2561
It is possible to calculate the typical current consumption based on the numbers from Table 32-1
on page 390 for other V
CC
and frequency settings than listed in Table 32-2.
32.2.1.1 Example 1
Calculate the expected current consumption in idle mode with USART0, TIMER1, and TWI
enabled at V
CC
= 2.0V and F = 1MHz. From Table 32-2, third column, we see that we need to
add 17% for the USART0, 24% for the TWI, and 10% for the TIMER1 module. Reading from Fig-
ure 32-6 on page 388, we find that the idle current consumption is ~0.15mA at V
CC
= 2.0V and F
= 1MHz. The total current consumption in idle mode with USART0, TIMER1, and TWI enabled,
gives:
Table 32-2. Additional Current Consumption (percentage) in Active and Idle mode
PRR bit
Additional Current consumption
compared to Active with external clock
Additional Current consumption
compared to Idle with external clock
PRUSART3 3.0% 17%
PRUSART2 3.0% 17%
PRUSART1 3.0% 17%
PRUSART0 3.0% 17%
PRTWI4.4% 24%
PRTIM5 1.8% 10%
PRTIM4 1.8% 10%
PRTIM3 1.8% 10%
PRTIM2 4.3% 23%
PRTIM1 1.8% 10%
PRTIM0 1.5% 8.0%
PRSPI 3.3% 18%
PRADC 4.5% 24%
ICCtotal 0.15mA 10.170.240.10+++ 0.227mA