at42qt1040 ATMEL Corporation, at42qt1040 Datasheet - Page 3

• Manufacturer Part Number: at42qt1040
• Description: Qtouch? 4-key Sensor Ic
• Manufacturer: ATMEL Corporation

1.2
Figure 1-1.
9524B–AT42–04/09
Example use of output pins
Follow regulator manufacturer's
recommended values for input
and output bypass capacitors (Creg).
Schematic
VUNREG
Typical Circuit
J3
5
4
3
2
1
Creg
RL0
RL1
RL2
RL3
5
4
3
2
1
Suggested regulator manufacturers:
Re
• Torex (XC6215 series)
• Seiko (S817 series)
• BCDSemi (AP2121 series)
•
•
•
VREG
GND
Section 3.1 on page
Section 3.5 on page
Section 3.3 on page
Figure 1-1
Creg
check the following sections for component values:
Add a 100 nF capacitor close to pin 9.
11
12
14
13
10
17
18
19
6
7
OUT0
OUT1
OUT2
OUT3
N/C
N/C
N/C
N/C
N/C
N/C
6:
7: Voltage levels
6: LED traces
Cs capacitors (Cs0 – Cs3)
QT1040
VDD
SNSK0
SNSK1
SNSK2
SNSK3
SNS0
SNS1
SNS2
SNS3
NOTES:
1) The central pad on the underside of the VQFN chip is a Vss pin and should be connected
2) It is important to place all Cs and Rs components physically near to the chip.
to ground. Do not put any other tracks underneath the body of the chip.
4
5
2
3
20
1
15
16
RAKS
Cs0
Cs1
Cs2
Cs3
RFS
Rs0
Rs1
Rs2
Rs3
VDD
VDD
SPEED SELECT
1
2
3
1
2
3
AKS SELECT
J1
J2
AT42QT1040
Key0
Key1
Key2
Key3
ON
OFF
FAST
SLOW
3