ATmega32A Atmel Corporation, ATmega32A Datasheet - Page 33

• Manufacturer Part Number: ATmega32A
• Manufacturer: Atmel Corporation

Specifications of ATmega32A

• Flash (kbytes): 32 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 32
• Ext Interrupts: 3
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 1
• 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): 2
• Eeprom (bytes): 1024
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 4
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

9. Power Management and Sleep Modes
9.1
9.2
8155C–AVR–02/11
Sleep Modes
Idle Mode
Sleep modes enable the application to shut down unused modules in the MCU, thereby saving
power. The AVR provides various sleep modes allowing the user to tailor the power consump-
tion to the application’s requirements.
Figure 8-1 on page 25
bution. The figure is helpful in selecting an appropriate sleep mode.
different clock options and their wake-up sources.
Table 9-1.
Notes:
To enter any of the six sleep modes, the SE bit in MCUCR must be written to logic one and a
SLEEP instruction must be executed. The SM2, SM1, and SM0 bits in the MCUCR Register
select which sleep mode (Idle, ADC Noise Reduction, Power-down, Power-save, Standby, or
Extended Standby) will be activated by the SLEEP instruction. See
summary.
If an enabled interrupt occurs while the MCU is in a sleep mode, the MCU wakes up. The MCU
is then halted for four cycles in addition to the start-up time, it executes the interrupt routine, and
resumes execution from the instruction following SLEEP. The contents of the Register File and
SRAM are unaltered when the device wakes up from sleep. If a Reset occurs during sleep
mode, the MCU wakes up and executes from the Reset Vector.
When the SM2:0 bits are written to 000, the SLEEP instruction makes the MCU enter Idle mode,
stopping the CPU but allowing SPI, USART, Analog Comparator, ADC, Two-wire Serial Inter-
Sleep Mode
Idle
ADC Noise
Reduction
Power-down
Power-save
Standby
Extended
Standby
1. External Crystal or resonator selected as clock source.
2. If AS
3. Only INT2 or level interrupt INT1 and INT0.
(1)
(1)
Active Clock Domains and Wake Up Sources in the Different Sleep Modes
2
Active Clock domains
bit in ASSR is set.
presents the different clock systems in the ATmega32A, and their distri-
X
X
X
X
X
X
X
(2)
(2)
Oscillators
X
X
X
X
X
X
X
X
(2)
(2)
(2)
(2)
X
X
X
X
X
X
(3)
(3)
(3)
(3)
(3)
Wake-up Sources
X
X
X
X
X
X
Table 9-2 on page 37
ATmega32A
X
X
Table 9-1
X
X
(2)
(2)
X
X
shows the
X
X
for a
X
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