Datasheet

PRR Bit Typical Numbers (µA)
V
CC
= 2V, F = 1 MHz V
CC
= 3V, F = 4 MHz V
CC
= 5V, F = 8 MHz
PRTIM1 3.50 23.0 55.3
PRTIM0 1.43 9.2 21.4
PRSPI 5.01 38.6 111.4
PRADC 6.34 45.7 123.6
Table 34-6. ATmega168A: Additional Current Consumption (Percentage) in Active and Idle mode
PRR bit Additional Current consumption
compared to Active with external clock
(Figure 34-95 and Figure 34-96)
Additional Current consumption
compared to Idle with external clock (see
Figure 34-100 and Figure 34-101)
PRUSART0 1.5% 8.9%
PRTWI 3.2% 19.5%
PRTIM2 2.4% 14.8%
PRTIM1 1.7% 10.3%
PRTIM0 0.7% 4.1%
PRSPI 2.9% 17.1%
PRADC 3.4% 20.3%
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
14.11.3 PRR
34.3.3.1 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 Additional Current Consumption (percentage) in Active and Idle mode in
the previous section, third column, we see that we need to add 10.3% for the TIMER1, 20.3% for the
ADC, and 17.1% for the SPI module. Reading from Figure Idle Supply Current vs. Low Frequency
(0.1-1.0MHz), we find that the idle current consumption is ~0.027mA at V
CC
= 2.0V and F = 1MHz. The
total current consumption in idle mode with TIMER1, ADC, and SPI enabled, gives:
I
CCtotal
 0.027mA(1+0.103+0.203+0.171)  0.040mA
ATmega48A/88A/168A
Typical Characteristics (TA = -40°C to 85°C)
© 2018 Microchip Technology Inc.
Datasheet Complete
DS40002007A-page 448