Touch International MulTI-Touch Quick setup guide

Document Number: 6500493 Rev. 1.1 Pg. 1
MulTI-Touch
Projected Capacitive Touch Screen
Integration Guide

Document Number: 6500493 Rev. 1.1 Pg. 2
The information provided in this document is intended as a guide only and is subject to change without
notice. Touch International is committed to continually advancing product designs; therefore, product specifications
may be subject to change without notification. Please contact your Touch International Sales Representative for the
most recent specification.
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not be reproduced or disclosed to third parties without the prior written consent of Touch International. Touch
International may have patents or pending patent applications, trademarks, copyrights or other intellectual property
rights covering subject matter in this document.
– IMPORTANT NOTICE –
A variety of factors can affect the performance and use of Touch International products. The customer is responsible
for evaluating the product and software to insure it is suitable for the intended application. Touch International
statements, engineering/technical information and recommendations are provided for the user’s convenience, but
their accuracy or completeness is not warranted.
Specifications are subject to change without notice. Touch International products and software are warranted to meet
their published specifications from the date of shipment and for the period stated in the specification.
The customer is responsible for determining whether the Touch International products and software are applicable to
the application and is suitable for its production process. In the event of a defective product, Touch International is
only obligated to cover failures due to defects in materials or workmanship that occur in normal use. Touch
International is not obligated to cover damage that occurs in shipment, failures that are caused by products not
supplied by Touch International, failures that result from accident, misuse, abuse, neglect, water damage,
mishandling, misapplication, faulty installation, set-up adjustments, improper maintenance, alteration, line power
surge, external product damage including field damage, modification or service not approved by Touch International
or damage that is attributable to acts of God.
Copyright © 2011 - Touch International - All Rights Reserved
Last Revision Date: 5/03/2011
Document Number: 6500493
Revision: 1.0

Document Number: 6500493 Rev. 1.1 Pg. 3
Document Revision History
Revision Page Content Revised By Date
1.0 1-13 Initial Release Mani Thangaraju 5/3/2011
1.1 1-13 Revision/Logo/Etc. Shaun Detmer 4/20/2014

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1.0 Manual Introduction
1.1 Safety
This symbol indicates potential hazards that can harm personnel.
This symbol indicates potential hazards that can damage the product.
1.2 Terms
The following terms and abbreviations may be unfamiliar and may appear in the manual. As such, they are
defined in Table 1.
Viewing Area This is the area of the Touch Screen that is visible after a bezel is mounted.
Active Area This is the area of the Touch Screen that will recognize a touch event.
Underlay A graphic to define keys and buttons for certain display applications.
ESD This refers to electrostatic discharge.
VHB This refers to a very high bond.
EMI This refers to electro-magnetic interference.
RFI This refers to radio frequency interference.
2.0 Touch Screen Kit
2.1 Components
Touch Screen
Touch Screen Controller
USB Mini Cable and/or RS232 Communication Cable and Power Cable
Adhesives
Figure 1: MulTI-Touch Screen Kit Components

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3.0 Touch Screen Maintenance
3.1 Cleaning the Touch Screen
Caution: Do not use any cleaners with chemicals that can corrode glass or damage the touch
screen permanently. When cleaning the touch screen, use a soft, lint free cloth to prevent
scratches and contamination. Avoid using sharp/hard objects.
Before integrating the touch screen, make certain it is properly cleaned. It is highly recommended that the
installation of the touch screen is performed in a clean room to prevent any contamination.
1. Wear powder free gloves before handling the touch screen.
2. Wear a grounded wrist band to prevent any static damage to electronic components.
3. Clean both sides of the touch screen with a non-abrasive anti-static solution (lens cleaner).
4. Clean both sides of the touch screen again with rubbing alcohol.
5. Repeat steps 3 and 4 as needed until the touch screen is free of all contaminants, such as
fingerprints or dust.
6. Allow the touch screen to fully dry before integrating.
4.0 Touch Screen Integration
1.1 Integrating the Touch Screen
Caution: Practice safety while integrating touch screens, controllers, LCDs and all other
components included in this document. Beware of sharp edges which can cut or harm people.
MulTI-Touch touch screens can be integrated in a variety of ways. The most general method of integrating
the Touch Screen with a display is presented in Figure 2.
Figure 2: Touch Screen and Controller Integration

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4.0 Touch Screen Integration (Continued)
4.2 Mounting the Touch Screen
The Projected Capacitive Touch Screen should be mounted to a display with an adhesive that is at least
.062” thick. To mount a bezel onto the Touch Screen, an adhesive that is at least .062” thick should also be
used.
The recommended adhesive is 3M 4956 VHB Tape. This adhesive can be provided by TI as P/N 1600136.
Please refer to Figures 2 and 3, which illustrate the mounting process.
Figure 3: Touch Screen Mounting
4.3 Touch Screen Placement and Alignment
When choosing a MulTI-Touch touch screen, ensure that its active area will fit with the active area of your
display. The active area of the sensor is enclosed by the edge sensor leads. Please see Figure 4 for more
details.
Carefully align the active area of the touch screen to the active area of the display. To ensure accurate
performance, the center X and Y points of the two active areas should be as close as possible to one
another. Typical integrations align the centers within ± .5 mm in both the X and Y positions. The better the
alignment, the more accurate the touch will be. Please refer to Figure 5, which illustrates the alignment.
Figure 4: Active Area Definition

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4.0 Touch Screen Integration (Continued)
4.3 Touch Screen Placement and Alignment
Figure 5: Aligning Active Areas When Mounting
4.4 Bezel and Gasket Restritions
A single perimeter sealing gasket is recommended to ensure a complete seal. Otherwise, liquids or other
contaminants may enter the product.
When desired, gasket strips may also be used.
Bezels and gaskets should not be placed or mounted within the viewing area of the touch screen by
more than 0.020 inches (0.5 mm). Doing so may adversely affect the performance of the touch screen.
Non-conductive and non-porous gaskets should be used.
4.5 Electro-Magnetic Interference (EMI)
The touch screen and controller should be mounted away from components that create electro-magnetic or
radio frequency interference. Refrain from mounting the controller near devices that generate signals in
the range of 50 kHz to 100 kHz, as well as transformers and backlight inverters. Mounting near these
devices can interfere with the performance of the touch screen and controller.
If a plastic bezel is utilized, metalizing and grounding the bezel will help minimize EMI and noise. If a
metal bezel is employed, make sure it is properly grounded.
To shield components from the EMI generated by the touch screen and controller, cover the outer edges of
the touch screen and its tails with copper tape. Ensure that the copper tape does not lie within the viewing
or active area of the touch screen when covering the sensor’s edges. The controller should be covered with
three layers of tape. First, Kapton tape, then copper tape, then Kapton tape again. All copper tape needs to
be properly grounded.

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4.0 Touch Screen Integration (Continued)
4.5 Underlay
A graphic underlay may be placed between the display and the touch screen. This underlay may be useful
in defining keys or buttons for special applications. An example is shown in Figure 6.
Figure 6: Graphic Underlay Example
5.0 Controller Integration
5.1 Mounting the Controller
Caution:
The controller is ESD sensitive. Please wear a grounded wrist strap while handling the
controller.
Make sure that the controller is grounded to the display’s casing or housing.
Mount the controller as far as possible from components that produce signals from 50 kHz to
100 kHz, as well as transformers and backlight inverters.
Nothing should contact the top and bottom sides of the controller; otherwise the controller may
short out.
The controller can be mounted in two ways. (See figures 7 and 8 for further information.)
1. Stand-offs with at least one grounded to the casing or housing.
2. Wire / cable grounded to the casing or housing

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5.0 Controller Integration (Continued)
5.1 Mounting the Controller
Figure 7: Grounded Stand-Off Figure 8: Grounded Cable
If height restrictions cannot accommodate the use of standoffs, thin gaskets may be used to mount the
controller, as long as the controller is properly grounded with a cable. Please refer to Figure 9 for this set
up.
Figure 9: Gasket Mounting with Grounded Cable

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6.0 Touch Screen Tails
6.1 Tail Guidelines
Keep touch screen tails away from components that create signals from 50kHz to 100kHz, as well as
transformers and backlight inverters.
Keep touch screen tails away from conductive materials if possible. Otherwise, the touch screen tails, or
the conductive surfaces should be shielded and separated from one another by at least 0.1”.
Shielding can be applied by placing Kapton or copper tape on the touch screen tails.
The touch screen tails should not bend at a radius less than 0.125”, as seen in Figure 10.
If the sensor tail runs through slots or around sharp edges, cushion the sharp edges to prevent damage to
the sensor tails. Please refer to Figure 11.
Figure 10: Touch Screen Tail Minimum Bend Radius
Figure 11: Cushion Edges Around the Touch Screen Tails