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Help me identify my touch panels

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Sobakava

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Touchscreen

I've touchscreen glasses for 128x128 T6963 LCD modules but I don't have any info about this touch-panels...

LCD module and touch panels are seperate. I've no problem with LCD module now...

For touch-panel:

It is a usual glass with a layer on it... There are two single row flat ribbon
cable & connectors. (One cable is 18pins...)

I can count the segments of the panel... It is 8 x 6 = 48 segment
panel.

How can I use it? There are 4wire touchscreen LCD interface ICs...

What can I do for my touch panel?

Regards
 

pisoiu

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Re: Touchscreen

Sobakava,
There are basically two kind of touchpanels. Those one for high area screens are analogue touchpanels (which can be resistive, capacitive or infrared). Those controllers for 4 wire touchpanels are dedicated for use with 4 wire resistive touchpanels. There are also 5 wire analog touchpanels available. Second type is what you have. Probably a matrix touchpanel. This mean that approx. above one character area of your LCD you have one crossing between a row and a column of your touchpanel. Look carefully at the glass above the lcd, and if you are looking in a certain angle you will see a reflection of the conductors from which the touchpanel is made. All you have to do is to identify the pins used for rows and those used for columns, and then make a circuit which is able to detect the resistance inserted between a row and a column when a pad is touched with the finger (few kiloohms).

/pisoiu
 

Sobakava

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Re: Touchscreen

There are 24 contacts...

there are 6 rows, 8 columns
I can see the traces on glass.

One 8pin group goes to columns
One 8pin group goes to rows
One 8pin group looks like shorted but I can not see anything with ohmmeter evet @ 2Mohm range...

I tried to measure resistance with a column pin and row pin @2Mhohm range... There is nothing....

Please see the photo of my panel...

How can I use this thing?

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pisoiu

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Re: Touchscreen

Hmm...strange, you should see some resistance between a row and a column when the finger is at their crossing. Try again with a wet finger, to increase conductivity. If this does not work also, then try to insert a AC voltage in a row pin, with frequency around few khz, and try to see with an oscilloscope on which column is returning that signal when the finger is at their crossing.

/pisoiu
 

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