QT60248C-ASG Atmel, QT60248C-ASG Datasheet - Page 61

• Manufacturer Part Number: QT60248C-ASG
• Description: IC TOUCH SENSOR 24KEY 32TQFP
• Manufacturer: Atmel
• Series: QMatrix™, QProx™r
• Type: Capacitiver

Specifications of QT60248C-ASG

• Number Of Inputs/keys: 24 Key
• Resolution (bits): 9, 11 b
• Data Interface: Serial, SPI™
• Voltage - Supply: 3 V ~ 5 V
• Current - Supply: 25mA
• Operating Temperature: -40°C ~ 105°C
• Mounting Type: Surface Mount
• Package / Case: 32-TQFP, 32-VQFP
• Output Type: *
• Interface: *
• Input Type: *
• For Use With: 427-1087 - BOARD EVAL QT60248-AS QMATRIX
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

6.3.4.3
Touch Sensors Design Guide
Wheel
To form a wheel, the design is simply is wrapped around to form a circle, with the X segments becoming
wedge shaped (see
many Y “circles” as necessary to ensure a maximum gap of 4 mm between them.
Figure 6-5.
Center diameter depends on
the number of Y traces,
the spacing of Y traces,
the number of X electrodes, etc.
Note the maximum outer arc length
0.1–0.5 mm
Gap Between
X Electrodes
Two-layer Small Wheel: Multiple Y Traces (Spatially Interpolated)
Figure
1.5–4 mm
X5
X6
2–4 mm
6-5). Note that, as with the Y “stripes” in the slider design, there should be as
X4
Y, 0.1
–0.5
X7
mm Width
Mutual-capacitance One-dimensional Sensors
X0
Y should connect on layer
below X if possible
X3
X2
Outer Arc
<8 mm
X1
10620D–AT42–04/09
6-7