Atmel Evaluation Kit AT91SAM9X35-EK AT91SAM9X35-EK Data Sheet
Product codes
AT91SAM9X35-EK
Evaluation Kit Hardware
4-80
Evaluation Kit (EK) User Guide
11115A–ATARM–27-Jul-11
4.4.3.3
Back Light
The back light voltage is generated from a CP2122ST boost converter. It is powered directly by the DC
5V from the EK board. The back light level is controlled by a PWM signal generated from the MPU
Device processor.
5V from the EK board. The back light level is controlled by a PWM signal generated from the MPU
Device processor.
Figure 4-57. Back Light Control
4.4.3.4
QTouch
The DM board carries a QTouch device piloted through a TWI interface. It manages four capacitive
touch buttons directly printed on the PCB.
touch buttons directly printed on the PCB.
There are dual footprints for the QTouch device, and SOIC is the default mounted one.
Figure 4-58. QTouch
50V
5V/217mA
24.5V/40mA
10V
VLED-
VLED+
C9
2.2u
2.2u
2 x 7 LEDs Back Light
2*20mA, 24.5V
5V_INTER
LCDPWM
C7
10u
10u
300mV
L1
22uH
22uH
R41
7R5
7R5
R40
10k
10k
MN1
CP2122ST
SW
1
GND
2
FB
3
SHDN#
4
VIN
5
D1
RB160M-60
60V/1A
880mA
TWD0
K2
KEY
C14
100n
K3
KEY
K4
KEY
TWCK0
MN5
QT1070_SOIC
VDD
1
MODE(VSS)
2
SDA
3
RESET
4
CHANGE
5
SCL
6
KEY 6
7
KEY 5
8
KEY 4
9
KEY 3
10
KEY 2
11
KEY 1
12
KEY 0
13
VSS
14
RESET#
R59
4.7k
DNP
R65
4.7k
R66
4.7k
R56
4.7k
R67
4.7k
3V3_LCD
R68
4.7k
R57
4.7k
DNP
R60
4.7k
DNP
R61
4.7k
DNP
R58
4.7k
DNP
TWD0
R62
4.7k
DNP
RESET#
3V3_LCD
CHANGE#
C16
100n
TWCK0
KEY 4
KEY 3
KEY 3
MN4
QT1070
DNP
NC4
7
NC3
10
NC2
18
NC1
19
NC0
20
SDA
12
CHANGE
14
RESET
13
NC5
6
SCL
15
KEY 4
1
KEY 3
2
KEY 2
3
KEY 1
4
KEY 0
5
VD
D
9
M
O
D
E
(VSS)
11
VSS
8
KEY 6
16
KEY 5
17
T
herm
a
l
21
KEY 2
KEY 1
KEY 1
K1
KEY
R63
10k
CHANGE#
3V3_LCD