Datasheet

PRR bit Additional Current consumption
compared to Active with external clock
(see Figure 34-1 and Figure 34-2)
Additional Current consumption
compared to Idle with external clock (see
Figure 34-6 and Figure 34-7)
PRTIM2 2.9% 15.7%
PRTIM1 2.1% 11.2%
PRTIM0 0.8% 4.2%
PRSPI 3.3% 17.6%
PRADC 4.2% 22.1%
It is possible to calculate the typical current consumption based on the numbers from the above table for
other V
CC
and frequency settings.
Related Links
14.12.3 PRR
34.1.3.1 Example
Calculate the expected current consumption in Idle mode with TIMER1, ADC, and SPI enabled at V
CC
=
2.0V and F = 1 MHz. From the table Additional Current Consumption (percentage) in Active and Idle
mode in the previous section, third column, we see that we need to add 11.2% for the TIMER1, 22.1% for
the ADC, and 17.6% for the SPI module. Reading from the figure Idle Supply Current vs. Low Frequency
(0.1-1.0 MHz), we find that the idle current consumption is ~0.028mA at V
CC
= 2.0V and F = 1 MHz. The
total current consumption in Idle mode with TIMER1, ADC, and SPI enabled, gives:
I
CCtotal
 0.028mA(1+0.112+0.221+0.176)  0.042mA
34.1.4 Power-Down Supply Current
Figure 34-11. ATmega48PA: Power-Down Supply Current vs. V
CC
(Watchdog Timer Disabled)
105°C
85°C
25°C
-40°C
0
0.
3
0.6
0.
9
1.2
1.5
1.
8
2.1
2.4
2.7
1.5 2 2.5 3 3.5 4 4.5 5 5.5
V
CC
(V)
I
CC
(µA)
ATmega48PA/88PA/168PA
Typical Characteristics (TA = -40°C to 105°C)
© 2018 Microchip Technology Inc.
Datasheet Complete
DS40002011A-page 404