11

Atmel | SMART SAM R21 [PRELIMINARY DATASHEET SUMMARY]

Atmel-42223AS–SAM-R21_Summary–07/2014

4.2

SAM R21E - QFN32

Note:

The large center pad underneath the QFN package is made of metal and internally connected to GND.

It should be soldered and connected to the digital ground on the board to ensure good mechanical stability.

It is not recommended to use the exposed paddle as a replacement of the regular GND pin.

PA16

17

PA17

18

PA18

19

PA19

20

DVDD

21

PA24

22

PA25

23

VDDIO

24

XTAL2

1

XTAL1

2

GNDANA

3

VDDANA

4

AVDD

5

GNDANA

6

PA06

7

PA07

8

DIGITAL PIN

ANALOG PIN

OSCILLATOR

GROUND

INPUT SUPPLY

REGULATED OUTPUT

RESET PIN

RF PIN

DIGITAL PIN/

SUPPLY

OSCILLATOR