Figure 147. Idle Supply Current vs. VCC (32 kHz External Oscillator)
IDLE SUPPLY CURRENT vs. VCC
32 kHz EXTERNAL OSCILLATOR
30
25
20
15
10
5
25 °C
0
1.5
2
2.5
3
3.5
4
4.5
5
5.5
VCC (V)
Supply Current of IO
modules
The tables and formulas below can be used to calculate the additional current consump-
tion for the different I/O modules in Active and Idle mode. The enabling or disabling of
the I/O modules are controlled by the Power Reduction Register. See “Power Reduction
Register” on page 37 for details.
Table 136.
Additional Current Consumption for the different I/O modules (absolute values)
PRR bit
Typical numbers
VCC = 2V, F = 1MHz
8.0 uA
VCC = 3V, F = 4MHz
VCC = 5V, F = 8MHz
220 uA
PRUSART0
PRTWI
51 uA
12 uA
11 uA
5.0 uA
4.0 uA
15 uA
12 uA
75 uA
72 uA
32 uA
24 uA
95 uA
75 uA
315 uA
PRTIM2
PRTIM1
PRTIM0
PRSPI
300 uA
130 uA
100 uA
400 uA
PRADC
315 uA
Table 137.
Additional Current Consumption (percentage) in Active and Idle mode
Additional Current consumption
compared to Active with external
clock
Additional Current consumption
compared to Idle with external
clock
PRR bit
PRUSART0
PRTWI
(see Figure 136 and Figure 137)
(see Figure 142 and Figure 143)
3.3ꢀ
4.8ꢀ
4.7ꢀ
18ꢀ
26ꢀ
25ꢀ
PRTIM2
304
ATmega48/88/168
2545D–AVR–07/04
ATMEL [ ATMEL ]
