User Manual

474
ATmega48A/PA/88A/PA/168A/PA/328/P [DATASHEET]
8271E–AVR–07/2012
It is possible to calculate the typical current consumption based on the numbers from Table 30-13 for other V
CC
and frequency settings than listed in Table 30-14.
30.7.3.1 Example
Calculate the expected current consumption in idle mode with TIMER1, ADC, and SPI enabled at V
CC
= 2.0V and
F = 1MHz. From Table 30-14, third column, we see that we need to add 14.5% for the TIMER1, 22.1% for the ADC,
and 15.7% for the SPI module. Reading from Figure 30-336 on page 496, we find that the idle current consumption
is ~0.055 mA at V
CC
= 2.0V and F = 1MHz. The total current consumption in idle mode with TIMER1, ADC, and SPI
enabled, gives:
30.7.4 Power-down Supply Current
Figure 30-293.ATmega328: Power-Down Supply Current vs. V
CC
(Watchdog Timer Disabled)
Table 30-14. ATmega328: Additional Current Consumption (percentage) in Active and Idle mode
PRR bit
Additional Current consumption
compared to Active with external
clock (see Figure 30-330 on page
493 and Figure 30-331 on page
493)
Additional Current consumption
compared to Idle with external
clock (see Figure 30-335 on page
495 and Figure 30-336 on page
496)
PRUSART0 1.4% 7.8%
PRTWI 3.0% 16.6%
PRTIM2 3.3% 17.8%
PRTIM1 2.7% 14.5%
PRTIM0 0.9% 4.8%
PRSPI 2.9% 15.7%
PRADC 4.1% 22.1%
ICCtotal 0.045 mA (1 + 0.145 + 0.221 + 0.157) 0.069 mA
85 °C
25 °C
-40 °C
0
0.2
0.4
0.6
0.8
1
1.2
1.5 2 2.5 3 3.5 4 4.5 5 5.5
V
CC
(V)
I
CC
(uA)