ATMEGA16U4-MU Atmel, ATMEGA16U4-MU Datasheet - Page 46

• Manufacturer Part Number: ATMEGA16U4-MU
• Description: MCU AVR 16K FLASH 16MHZ 44-QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA16U4-MU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 26
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-VQFN
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32ATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVRATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: ATMEGA16U4-16MU; ATMEGA16U4-16MU

7.7.1
7.7.2
7766F–AVR–11/10
Power Reduction Register 0 - PRR0
Power Reduction Register 1 - PRR1
• Bit 7 - PRTWI: Power Reduction TWI
Writing a logic one to this bit shuts down the TWI by stopping the clock to the module. When
waking up the TWI again, the TWI should be re initialized to ensure proper operation.
• Bit 6 - Res: Reserved bit
This bits is reserved and will always read as zero.
• Bit 5 - PRTIM0: Power Reduction Timer/Counter0
Writing a logic one to this bit shuts down the Timer/Counter0 module. When the Timer/Counter0
is enabled, operation will continue like before the shutdown.
• Bit 4 - Res: Reserved bit
This bit is reserved and will always read as zero.
• Bit 3 - PRTIM1: Power Reduction Timer/Counter1
Writing a logic one to this bit shuts down the Timer/Counter1 module. When the Timer/Counter1
is enabled, operation will continue like before the shutdown.
• Bit 2 - PRSPI: Power Reduction Serial Peripheral Interface
Writing a logic one to this bit shuts down the Serial Peripheral Interface by stopping the clock to
the module. When waking up the SPI again, the SPI should be re initialized to ensure proper
operation.
• Bit 1 - Res: Reserved bit
These bits are reserved and will always read as zero.
• Bit 0 - PRADC: Power Reduction ADC
Writing a logic one to this bit shuts down the ADC. The ADC must be disabled before shut down.
The analog comparator cannot use the ADC input MUX when the ADC is shut down.
• Bit 7 - PRUSB: Power Reduction USB
Writing a logic one to this bit shuts down the USB by stopping the clock to the module. When
waking up the USB again, the USB should be re initialized to ensure proper operation.
• Bit 6..5 - Res: Reserved bits
These bits are reserved and will always read as zero.
Bit
Read/Write
Initial Value
Bit
Read/Write
Initial Value
7
PRUSB
R/W
0
7
PRTWI
R/W
0
6
PRTIM2
R/W
0
6
–
R
0
5
–
R
0
5
PRTIM0
R/W
0
4
PRTIM4
R
0
4
–
R
0
3
PRTIM1
R/W
0
3
PRTIM3
0
R/W
2
PRSPI
R/W
0
2
–
R
0
1
-
R
0
1
–
R
0
ATmega16/32U4
0
PRUSART1
R/W
0
0
PRADC
R/W
0
PRR0
PRR1
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