atxmega192a1-cu ATMEL Corporation, atxmega192a1-cu Datasheet - Page 17

• Manufacturer Part Number: atxmega192a1-cu
• Description: Atxmega64a1 8/16 Bit Microcontroller With 64/128/192/256k Bytes In-system Programmable Flash
• Manufacturer: ATMEL Corporation

11. Power Management and Sleep Modes
11.1
11.2
11.3
11.3.1
11.3.2
11.3.3
11.3.4
8067A–AVR–02/08
Features
Overview
Sleep Modes
Idle Mode
Power-down Mode
Power-save Mode
Standby Mode
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The XMEGA A1 provides various sleep modes tailored to reduce power consumption to a mini-
mum. All sleep modes are accessible from Active mode. In Active mode the CPU is executing
application code. The application code decides when and what sleep mode to enter. Interrupts
from enabled peripherals and all enabled reset sources can restore the microcontroller from
sleep to Active mode. This is called a wake-up
In addition Power Reduction Registers (PRR) provides a method to stop the clock to individual
peripherals from software. When this is done the current state of the peripheral is frozen and
there is no power consumption from the peripheral.
In Idle mode the CPU and Non-Volatile Memory are stopped, but all peripherals including the
Interrupt Controller, Event System and DMA Controller are kept running.
Interrupt request from all enabled interrupts will wake the device.
In Power-down mode all system clock sources, including the Real Time Counter clock source
are stopped. This allows operation of asynchronous modules only. The only interrupts that can
wake up the MCU are the Two Wire Interface address match interrupts, and asynchronous port
interrupts.
Power-save mode is identical to Power-down, with one exception:
If the Real Time Counter (RTC) is enabled, it will keep running during sleep and the device can
also wake up from either RTC Overflow or Compare Match interrupt.
Standby mode is identical to Power-down with the exception that the system clock sources are
kept running, while the CPU, Peripheral and RTC clocks are stopped. This reduces the wake-up
time when external crystals or resonators are used.
5 sleep modes
Power Reduction register to disable clock to unused peripheral
– IDLE
– Power-down
– Power-save
– Standby
– Extended standby
ATxmega A1
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