ATQT600 Atmel, ATQT600 Datasheet - Page 8

• Manufacturer Part Number: ATQT600
• Description: KIT EVAL TOUCH FOR QT600
• Manufacturer: Atmel
• Series: QTouch™r

Specifications of ATQT600

• Sensor Type: Touch Screen
• Interface: USB
• Embedded: Yes, Other
• Utilized Ic / Part: ATtiny88, ATmega324PA, ATxmega128A1
• Processor To Be Evaluated: ATtiny88, ATmega324, ATxmega128
• Data Bus Width: 8 bit, 16 bit
• Interface Type: USB
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Operating Supply Voltage: 1.6 V to 3.6 V
• Silicon Manufacturer: Atmel
• Kit Application Type: Sensor
• Application Sub Type: Touch Sensor
• Kit Contents: USB Bridge, MCU Cards, Touchpad Cards
• Svhc: No SVHC (15-Dec-2010)
• Mcu Supported Families: ATtiny88,
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Supply: -
• Sensitivity: -
• Sensing Range: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

10620D–AT42–04/09
Introduction To Sensor Design
1.3
1.4
1-2
Dimension Groups
Some Important Theory
In addition to the self- and mutual-capacitance types described in
into three groups, depending on the number of dimensions they use (see



When considering the design of a sensor, you will need to consider both the sensor type and the
dimension group, making six possible combinations in total. The combinations for zero-dimensional and
one-dimensional sensors are discussed individually in
are not covered by this guide. For information on designing two-dimensional sensors, please contact
Atmel’s Touch Technology Division.
Figure 1-1.
You will need to be aware of the following terms when reading this document:







Zero Dimensional Sensors
Single point of contact
Key
Zero-dimensional sensors
A zero-dimensional sensor is one that represents a single point of contact. The typical implementation
of a zero-dimensional sensor is a key.
One-dimensional sensors
A one-dimensional sensor is one that detects the linear movement of a finger during touch (that is,
along a single axis). Typical implementations of one-dimensional sensors are sliders and wheels.
Two-dimensional sensors 
A two-dimensional sensor is one that detects the movement of a finger during touch along two axes.
Typical implementations of two-dimensional sensors are touchscreens and touchpads.
Cx: The electrode’s natural capacitance, separate from any parasitic capacitance


T: The thickness of the overlying panel in meters (see
A: The area of the touched region in square meters (see
Cp: Any parasitic capacitance added in parallel with Cx
SNR: Signal to noise ratio: a measure of the quality of the capacitive measurement
r
0
: The relative dielectric constant of the overlying panel material (see
: The capacitance per meter of free space, defined as 8.85 x 10
Sensor Dimensions
One Dimensional Sensors
Movement in one direction
Slider
Wheel
Section 3
Figure
Figure
1-2)
Two Dimensional Sensors
Movement in two directions
to
Touchscreen/
Touchpad
Section
1-2)
Section
-12
F/m
Figure 1-2 on page
Figure
1.2, sensors can also be split
Touch Sensors Design Guide
6; two-dimensional sensors
1-1):
1-3)