ATmega169P
Table 28-2. Additional Current Consumption (percentage) in Active and Idle mode
Additional Current consumption
compared to Active with external clock
(see Figure 28-1 and Figure 28-2)
Additional Current consumption
compared to Idle with external clock
(see Figure 28-6 and Figure 28-7)
PRR bit
PRSPI
3.2ꢀ
5.6ꢀ
10.8ꢀ
18.6ꢀ
41.7ꢀ
PRTIM1
PRLCD
12.5ꢀ
It is possible to calculate the typical current consumption based on the numbers from Table 28-2
for other VCC and frequency settings than listed in Table 28-1.
28.3.0.1
Example 1
Calculate the expected current consumption in idle mode with USART0, TIMER1, and SPI
enabled at VCC = 3.0V and F = 1MHz. From Table 28-2, second column, we see that we need to
add 12.4ꢀ for the USART0, 10.8ꢀ for the SPI, and 18.6ꢀ for the TIMER1 module. Reading
from Figure 28-6, we find that the idle current consumption is ~0.18mA at VCC = 3.0V and F =
1MHz. The total current consumption in idle mode with USART0, TIMER1, and SPI enabled,
gives:
ICCtotal ≈ 0,18mA • (1 + 0,124 + 0,108 + 0,186) ≈ 0,26mA
28.4 Power-down Supply Current
Figure 28-11. Power-down Supply Current vs. VCC (Watchdog Timer Disabled)
POWER-DOWN SUPPLY CURRENT vs. VCC
WATCHDOG TIMER DISABLED
1.60
1.40
1.20
1.00
0.80
0.60
0.40
0.20
0.00
85˚C
-40˚C
25˚C
1.5
2.0
2.5
3.0
3.5
CC (V)
4.0
4.5
5.0
5.5
V
341
8018A–AVR–03/06
ATMEL [ ATMEL ]
