Atmel Xplained Evaluation Board ATXMEGAA3BU-XPLD ATXMEGAA3BU-XPLD Data Sheet

 

8394B-AVR-02/12 

The Atmel AVR XMEGA-A3BU Xplained has an external Atmel AVR AT45DB642D 
DataFlash device mounted. A footprint is also available for adding an industrial 
standard serial flash like the AT25 series from Atmel. Compatible serial flash devices 
for both footprints are listed in 

 and the connection to the MCU is shown in 

. 

The footprints share the same SPI lines including the chip select, and therefore it is 
not possible to mount devices on both footprints at the same time. 

Table 5-1. Serial flash connection. 

PD1 SCK 

PD3 MOSI 

PD2 MISO 

PF4 SS 

Table 5-2. Compatible devices for the footprints. 

AT45DB64D2-CNU (mounted) 

AT25DF641A-SH 

AT45DB321D-MWU AT25DF321A-SH 

AT45DB161D-SS AT25DF161-SH 

AT45DB081D-SS AT25DF081-SSH 

AT45DB041D-SS AT25DF021-SSH 

AT45DB021D-SS  

AT45DB011D-SS  

The XMEGA-A3BU Xplained kit has one Atmel QTouch button and the connection to 
the Atmel AVR XMEGA is shown in 

. The QTouch sensor, a copper fill, is 

located on the second layer of the board (same as GND layer). The sensor is 
shielded by the third layer (VCC layer) and therefore the sensor is not affected by any 
touches from the back side of the board. 

Table 5-3. QTouch button connection. 

PF6 SNS 

PF7 SNSK 

The battery backup system backs up the RTC of the XMEGA. It consists of a coin cell 
battery, a battery holder and a jumper that can be used to disconnect the battery from 
the XMEGA. A manganese dioxide lithium battery (CR1220) from Panasonic with a 
nominal voltage of 3V and nominal capacity of 35mAh is used in this design. In order