Datasheet
Table Of Contents
- Features
- 1. Ordering Information
- 2. Pinout/Block Diagram
- 3. Overview
- 4. Resources
- 5. Capacitive touch sensing
- 6. AVR CPU
- 7. Memories
- 8. DMAC – Direct Memory Access Controller
- 9. Event System
- 10. System Clock and Clock options
- 10.1 Features
- 10.2 Overview
- 10.3 Clock Sources
- 10.3.1 32kHz Ultra Low Power Internal Oscillator
- 10.3.2 32.768kHz Calibrated Internal Oscillator
- 10.3.3 32.768kHz Crystal Oscillator
- 10.3.4 0.4 - 16MHz Crystal Oscillator
- 10.3.5 2MHz Run-time Calibrated Internal Oscillator
- 10.3.6 32MHz Run-time Calibrated Internal Oscillator
- 10.3.7 External Clock Sources
- 10.3.8 PLL with 1x-31x Multiplication Factor
- 11. Power Management and Sleep Modes
- 12. System Control and Reset
- 13. WDT – Watchdog Timer
- 14. Interrupts and Programmable Multilevel Interrupt Controller
- 15. I/O Ports
- 16. TC0/1 – 16-bit Timer/Counter Type 0 and 1
- 17. TC2 - Timer/Counter Type 2
- 18. AWeX – Advanced Waveform Extension
- 19. Hi-Res – High Resolution Extension
- 20. RTC – 16-bit Real-Time Counter
- 21. USB – Universal Serial Bus Interface
- 22. TWI – Two-Wire Interface
- 23. SPI – Serial Peripheral Interface
- 24. USART
- 25. IRCOM – IR Communication Module
- 26. AES and DES Crypto Engine
- 27. CRC – Cyclic Redundancy Check Generator
- 28. ADC – 12-bit Analog to Digital Converter
- 29. DAC – 12-bit Digital to Analog Converter
- 30. AC – Analog Comparator
- 31. Programming and Debugging
- 32. Pinout and Pin Functions
- 33. Peripheral Module Address Map
- 34. Instruction Set Summary
- 35. Packaging information
- 36. Electrical Characteristics
- 36.1 ATxmega16A4U
- 36.1.1 Absolute Maximum Ratings
- 36.1.2 General Operating Ratings
- 36.1.3 Current consumption
- 36.1.4 Wake-up time from sleep modes
- 36.1.5 I/O Pin Characteristics
- 36.1.6 ADC characteristics
- 36.1.7 DAC Characteristics
- 36.1.8 Analog Comparator Characteristics
- 36.1.9 Bandgap and Internal 1.0V Reference Characteristics
- 36.1.10 Brownout Detection Characteristics
- 36.1.11 External Reset Characteristics
- 36.1.12 Power-on Reset Characteristics
- 36.1.13 Flash and EEPROM Memory Characteristics
- 36.1.14 Clock and Oscillator Characteristics
- 36.1.14.1 Calibrated 32.768kHz Internal Oscillator characteristics
- 36.1.14.2 Calibrated 2MHz RC Internal Oscillator characteristics
- 36.1.14.3 Calibrated and tunable 32MHz internal oscillator characteristics
- 36.1.14.4 32kHz Internal ULP Oscillator characteristics
- 36.1.14.5 Internal Phase Locked Loop (PLL) characteristics
- 36.1.14.6 External clock characteristics
- 36.1.14.7 External 16MHz crystal oscillator and XOSC characteristic
- 36.1.14.8 External 32.768kHz crystal oscillator and TOSC characteristics
- 36.1.15 SPI Characteristics
- 36.1.16 Two-Wire Interface Characteristics
- 36.2 ATxmega32A4U
- 36.2.1 Absolute Maximum Ratings
- 36.2.2 General Operating Ratings
- 36.2.3 Current consumption
- 36.2.4 Wake-up time from sleep modes
- 36.2.5 I/O Pin Characteristics
- 36.2.6 ADC characteristics
- 36.2.7 DAC Characteristics
- 36.2.8 Analog Comparator Characteristics
- 36.2.9 Bandgap and Internal 1.0V Reference Characteristics
- 36.2.10 Brownout Detection Characteristics
- 36.2.11 External Reset Characteristics
- 36.2.12 Power-on Reset Characteristics
- 36.2.13 Flash and EEPROM Memory Characteristics
- 36.2.14 Clock and Oscillator Characteristics
- 36.2.14.1 Calibrated 32.768kHz Internal Oscillator characteristics
- 36.2.14.2 Calibrated 2MHz RC Internal Oscillator characteristics
- 36.2.14.3 Calibrated and tunable 32MHz internal oscillator characteristics
- 36.2.14.4 32kHz Internal ULP Oscillator characteristics
- 36.2.14.5 Internal Phase Locked Loop (PLL) characteristics
- 36.2.14.6 External clock characteristics
- 36.2.14.7 External 16MHz crystal oscillator and XOSC characteristic
- 36.2.14.8 External 32.768kHz crystal oscillator and TOSC characteristics
- 36.2.15 SPI Characteristics
- 36.2.16 Two-Wire Interface Characteristics
- 36.3 ATxmega64A4U
- 36.3.1 Absolute Maximum Ratings
- 36.3.2 General Operating Ratings
- 36.3.3 Current consumption
- 36.3.4 Wake-up time from sleep modes
- 36.3.5 I/O Pin Characteristics
- 36.3.6 ADC characteristics
- 36.3.7 DAC Characteristics
- 36.3.8 Analog Comparator Characteristics
- 36.3.9 Bandgap and Internal 1.0V Reference Characteristics
- 36.3.10 Brownout Detection Characteristics
- 36.3.11 External Reset Characteristics
- 36.3.12 Power-on Reset Characteristics
- 36.3.13 Flash and EEPROM Memory Characteristics
- 36.3.14 Clock and Oscillator Characteristics
- 36.3.14.1 Calibrated 32.768kHz Internal Oscillator characteristics
- 36.3.14.2 Calibrated 2MHz RC Internal Oscillator characteristics
- 36.3.14.3 Calibrated and tunable 32MHz internal oscillator characteristics
- 36.3.14.4 32kHz Internal ULP Oscillator characteristics
- 36.3.14.5 Internal Phase Locked Loop (PLL) characteristics
- 36.3.14.6 External clock characteristics
- 36.3.14.7 External 16MHz crystal oscillator and XOSC characteristic
- 36.3.14.8 External 32.768kHz crystal oscillator and TOSC characteristics
- 36.3.15 SPI Characteristics
- 36.3.16 Two-Wire Interface Characteristics
- 36.4 ATxmega128A4U
- 36.4.1 Absolute Maximum Ratings
- 36.4.2 General Operating Ratings
- 36.4.3 Current consumption
- 36.4.4 Wake-up time from sleep modes
- 36.4.5 I/O Pin Characteristics
- 36.4.6 ADC characteristics
- 36.4.7 DAC Characteristics
- 36.4.8 Analog Comparator Characteristics
- 36.4.9 Bandgap and Internal 1.0V Reference Characteristics
- 36.4.10 Brownout Detection Characteristics
- 36.4.11 External Reset Characteristics
- 36.4.12 Power-on Reset Characteristics
- 36.4.13 Flash and EEPROM Memory Characteristics
- 36.4.14 Clock and Oscillator Characteristics
- 36.4.14.1 Calibrated 32.768kHz Internal Oscillator characteristics
- 36.4.14.2 Calibrated 2MHz RC Internal Oscillator characteristics
- 36.4.14.3 Calibrated and tunable 32MHz internal oscillator characteristics
- 36.4.14.4 32kHz Internal ULP Oscillator characteristics
- 36.4.14.5 Internal Phase Locked Loop (PLL) characteristics
- 36.4.14.6 External clock characteristics
- 36.4.14.7 External 16MHz crystal oscillator and XOSC characteristic
- 36.4.14.8 External 32.768kHz crystal oscillator and TOSC characteristics
- 36.4.15 SPI Characteristics
- 36.4.16 Two-Wire Interface Characteristics
- 36.1 ATxmega16A4U
- 37. Typical Characteristics
- 37.1 ATxmega16A4U
- 37.1.1 Current consumption
- 37.1.2 I/O Pin Characteristics
- 37.1.3 ADC Characteristics
- 37.1.4 DAC Characteristics
- 37.1.5 Analog Comparator Characteristics
- 37.1.6 Internal 1.0V reference Characteristics
- 37.1.7 BOD Characteristics
- 37.1.8 External Reset Characteristics
- 37.1.9 Power-on Reset Characteristics
- 37.1.10 Oscillator Characteristics
- 37.1.11 Two-Wire Interface characteristics
- 37.1.12 PDI characteristics
- 37.2 ATxmega32A4U
- 37.2.1 Current consumption
- 37.2.2 I/O Pin Characteristics
- 37.2.3 ADC Characteristics
- 37.2.4 DAC Characteristics
- 37.2.5 Analog Comparator Characteristics
- 37.2.6 Internal 1.0V reference Characteristics
- 37.2.7 BOD Characteristics
- 37.2.8 External Reset Characteristics
- 37.2.9 Power-on Reset Characteristics
- 37.2.10 Oscillator Characteristics
- 37.2.11 Two-Wire Interface characteristics
- 37.2.12 PDI characteristics
- 37.3 ATxmega64A4U
- 37.3.1 Current consumption
- 37.3.2 I/O Pin Characteristics
- 37.3.3 ADC Characteristics
- 37.3.4 DAC Characteristics
- 37.3.5 Analog Comparator Characteristics
- 37.3.6 Internal 1.0V reference Characteristics
- 37.3.7 BOD Characteristics
- 37.3.8 External Reset Characteristics
- 37.3.9 Power-on Reset Characteristics
- 37.3.10 Oscillator Characteristics
- 37.3.11 Two-Wire Interface characteristics
- 37.3.12 PDI characteristics
- 37.4 ATxmega128A4U
- 37.4.1 Current consumption
- 37.4.2 I/O Pin Characteristics
- 37.4.3 ADC Characteristics
- 37.4.4 DAC Characteristics
- 37.4.5 Analog Comparator Characteristics
- 37.4.6 Internal 1.0V reference Characteristics
- 37.4.7 BOD Characteristics
- 37.4.8 External Reset Characteristics
- 37.4.9 Power-on Reset Characteristics
- 37.4.10 Oscillator Characteristics
- 37.4.11 Two-Wire Interface characteristics
- 37.4.12 PDI characteristics
- 37.1 ATxmega16A4U
- 38. Errata
- 39. Datasheet Revision History
- Table of Contents

27
XMEGA A4U [DATASHEET]
Atmel-8387H-AVR-ATxmega16A4U-34A4U-64A4U-128A4U-Datasheet_09/2014
12.4.2 Brownout Detection
The on-chip brownout detection (BOD) circuit monitors the V
CC
level during operation by comparing it to a fixed,
programmable level that is selected by the BODLEVEL fuses. If disabled, BOD is forced on at the lowest level during
chip erase and when the PDI is enabled.
12.4.3 External Reset
The external reset circuit is connected to the external RESET pin. The external reset will trigger when the RESET pin
is driven below the RESET
pin threshold voltage, V
RST
, for longer than the minimum pulse period, t
EXT
. The reset will
be held as long as the pin is kept low. The RESET
pin includes an internal pull-up resistor.
12.4.4 Watchdog Reset
The watchdog timer (WDT) is a system function for monitoring correct program operation. If the WDT is not reset from
the software within a programmable timeout period, a watchdog reset will be given. The watchdog reset is active for
one to two clock cycles of the 2MHz internal oscillator. For more details see “WDT – Watchdog Timer” on page 28.
12.4.5 Software Reset
The software reset makes it possible to issue a system reset from software by writing to the software reset bit in the
reset control register.The reset will be issued within two CPU clock cycles after writing the bit. It is not possible to
execute any instruction from when a software reset is requested until it is issued.
12.4.6 Program and Debug Interface Reset
The program and debug interface reset contains a separate reset source that is used to reset the device during
external programming and debugging. This reset source is accessible only from external debuggers and
programmers.