ATmega644P Atmel Corporation, ATmega644P Datasheet - Page 368

• Manufacturer Part Number: ATmega644P
• Manufacturer: Atmel Corporation

Specifications of ATmega644P

• Flash (kbytes): 64 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 32
• Ext Interrupts: 32
• Usb Speed: No
• Usb Interface: No
• Spi: 3
• Twi (i2c): 1
• Uart: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 4
• Eeprom (bytes): 2048
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

26.2.3
Example
8011O–AVR–07/10
Supply Current of I/O modules
The tables and formulas below can be used to calculate the additional current consumption 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
page 48
Table 26-3.
Table 26-4.
It is possible to calculate the typical current consumption based on the numbers from
on page 368
Calculate the expected current consumption in idle mode with TIMER1, ADC, and SPI enabled
at V
to add 9.7% for the TIMER1, 17.7% for the ADC, and 10.4% for the SPI module. Reading from
Figure 26-53 on page
and F = 1 MHz. The total current consumption in idle mode with TIMER1, ADC, and SPI
enabled, gives:
PRR bit
PRUSART1
PRUSART0
PRTWI
PRTIM2
PRTIM1
PRTIM0
PRADC
PRSPI
PRR bit
PRUSART1
PRUSART0
PRTWI
PRTIM2
PRTIM1
PRTIM0
PRADC
PRSPI
CC
= 2.0V and F = 1 MHz. From
for details.
for other V
Additional Current Consumption for the different I/O modules (absolute values)
Additional Current Consumption (percentage) in Active and Idle mode
Typical numbers
Additional Current consumption
compared to Active with external
clock (see
363
363)
V
CC
I
CC
365, we find that the idle current consumption is ~0.125 mA at V
and
= 2V, F = 1 MHz
CC
total
14.6 µA
11.7 µA
21.1 µA
10.7 µA
7.8 µA
7.6 µA
9.9 µA
6.0 µA
Figure 26-49 on page
and frequency settings than listed in
≈
Figure 26-48 on page
0.125 mA (1+ 0.097 + 0.177 + 0.104)
2.1 %
2.2%
3.1%
3.8%
2.6%
1.6%
4.8%
2.8%
Table 26-4 on page
⋅
V
CC
= 3V, F = 4 MHz
114.5 µA
50.0 µA
51.2 µA
73.3 µA
91.3 µA
64.0 µA
39.2 µA
67.7 µA
ATmega164P/324P/644P
Additional Current consumption
compared to Idle with external
clock (see
365
366)
”PRR – Power Reduction Register” on
368, third column, we see that we need
and
Figure 26-54 on page
Table 26-3 on page
≈
Figure 26-53 on page
0.172 mA
V
11.2%
14.1%
17.7%
10.4%
7.6%
8.0%
9.7%
6.1%
CC
= 5V, F = 8 MHz
215.5 µA
237.2 µA
309.3 µA
393.0 µA
271.7 µA
176.3 µA
437.2 µA
288.2 µA
368.
Table 26-4
CC
= 2.0V
368