ATSAM4S-EK2 Atmel, ATSAM4S-EK2 Datasheet - Page 19

• Manufacturer Part Number: ATSAM4S-EK2
• Description: Development Boards & Kits - ARM EVAL KIT SAM4S8 & SAM4S16
• Manufacturer: Atmel

Specifications of ATSAM4S-EK2

• Rohs: yes
• Product: Evaluation Kits
• Tool Is For Evaluation Of: SAM4SD32C
• Core: ARM Cortex M4
• Interface Type: RS-232, USB
• Operating Supply Voltage: 5 V

4.3.12.2 Analog Input
4.3.12.3 Analog Output
4.3.13
4.3.13.1 Keys
SAM4S-EK2 User Guide
QTouch Elements
The BNC connector CN1 is connected to the ADC port PB1 as an external analog input. An on-board 50-
Ohm resistor termination can be applied by closing jumper JP16. A low pass filter can be implemented
for the BNC connector CN1 by replacing R94 and C78 with custom resistor and capacitor values,
depending on your application requirements.
A 10-KOhm potentiometer (VR1) is also connected to this channel to implement an easy access to ADC
programming and debugging (or implement an analog user control like display brightness, volume, etc.).
Either of these two functions can be selected by jumper JP18.
Figure 4-16. ADC Input
The BNC connector CN2 is connected to the DAC port PB13 and provides an external analog output. An
on-board 50-Ohm resistor termination can be enabled by closing jumper JP21. A filter can be imple-
mented on this output channel by replacing R106 and C90 with appropriate resistor and capacitor
values, depending on the application requirements.
Figure 4-17. DAC Output
QTouch keys consist in a series of sensors formed by the association of a copper area and the capaci-
tive effect of human fingers approaching it.
The SAM4S-EK2 implements five individual capacitive touch keys (UP, DOWN, RIGHT, LEFT and
VALID) using five pairs of PIO.
CN2
BNC
CN1
BNC
10 K V R
VR1
DGND
DG ND
VCC3 3
DG ND
R109
49.9R
JP21
Header2
R9 6
49 .9R
JP 16
He ade r2
2
Potentiometer
Clockwise 2-->3
R9 4
0R
C90
C8 9
10 nF
R106
0R
AUDIO_OUTL
2.2uF
C7 8
10 nF
JP 18
JP30
AD C
DAC
2
2
AD5
DAC1
Evaluation Kit Hardware
PB 1
PB13
11176A–ATARM–24-Sep-12
4-12