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Touch Sensitivity Comparison


New member
I currently have a 2.8" Touch LCD from 4DSystems out of Australia. They are fairly expensive but they come with a programmable chip on them that allows them to operate independent of any other controller even though I am using a PIC for other functions.

I am running into two problems.

First, I need my project to fit into one of these cases: http://www.polycase.com/vm-24

While the module itself will just barely fit and their slightly smaller 2.4" will also fit, it is a very tight squeeze to fit in the rest of my components including a PIC Micro Controller (currently a through hole 16F but will likely upgrade to an SMD 18F), a rechargeable Li-Po, an RF Transceiver, a Splatch antenna and various support components.

The second issue is with the touch sensitivity. If I use a Stylis or a Fingernail, I have very good response from their display. If I use my finger, I have to really apply some force to get it to pick up the touch. I am only using fairly large buttons for navigation and do not require any kind of fine touch.

So that led me to look a little deeper. I found some modules that have a PIC 18F and built in Audio etc. Once again the problem is size. Like the 4D display, these come with a bunch of extras (audio, USB, etc) that I don't need.

So now here I am on this site and so far I like what I see. Barebones display that allows me to put what I want with it and dimensionaly the CFAF240320K-T-TS is perfect.

So a couple of questions, first, keeping in mind that I don't need extremely accurate touch, can I use a fingertip to touch large buttons without having to use brute force to recognize the touch?

How exactly would this be attached to a board. Not electrically, I get that, I am more concerned about physically mounting it to a PCB. conceptually what I have in my head is glued to one side of a PCB and the connection is wrapped around to the component side. I wouldn't be able to use a simple two layer PCB but I can deal with that. This question is more to get me past a proof of concept stage.

Sorry for the extra long post. I hope someone has the patience to get through it and help me out.

Thanks in advance,

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