What touch controller is used on the STM32F439I Eval Board

kartik · ‎2014-04-08

Posted on April 08, 2014 at 20:29

We are trying to put an embedded device which can drive a 4.3'' LCD with a capacitive touch overlay. Looking at the STM32F439 discovery platform, I see there is a 5.7'' LCD with a capacitive touch overlay. We would like to use this platform and be able to swap in a 4.3'' LCD. Eventually, we would like our production platform to be built based on this eval board and so I looked through the schematics and the BOM, however there is no mention of the touch controller used. I see references to a touch controller but no controller specifically. How is capacitive touch implemented on the STM32F439 discovery evaluation board.

Thanks

Kartik

#stm32f439 #stm-touch

Thierry GUILHOT · ‎2014-04-08

Posted on April 08, 2014 at 23:15

Hello,

The LCD display available on the STM32F439I Eval Board is using a standard 4-wire resitive touch screen. It is not a capacitive one! This touch screen is managed using a STMPE811QTR controller from ST. It is driven using a standard I2C interface. You can directly find further information on this device from our web site.

Best Regards,

Thierry,

kartik · ‎2014-04-08

Posted on April 09, 2014 at 00:26

Hi Thierry,

Here is the link to the

http://www.st.com/web/en/catalog/tools/PF259094

eval board on the ST site. It says it has a 5.7'' capacitive touch. We saw this on display at the EELive trade show in San Jose last week.

Thanks

Kartik

Thierry GUILHOT · ‎2014-04-08

Posted on April 09, 2014 at 08:28

Hi Kartik,

Sorry, I had a look to a different board. You are right this one is using a projected capacitive touch panel. It is driven by a TS3510 controller from ENE Technology Inc. I've attached the specification of the LCD and touch controller.

Best Regards,

Thierry,

kartik · ‎2014-04-10

Posted on April 10, 2014 at 19:37

Hi Thierry,

Thank you very much for your answer. It really helped us a lot. I have a few more related questions.

Would you know how difficult it would be to swap the AMP 5.7'' display with another display from AMP but a 4.3''. For instance the

http://www.ampdisplay.com/documents/pdf/AM-480272H5TMQW-T01H-L.pdf

It seems to be like the original display on board except with different brightness level and display modes. Would there be any changes that need to be made to the board itself or is it just a matter of switching the displays? Also would the touch controller need to be updated for the different sized touch panel? Finally what is your estimate of the effort involved LCD driver changes that will be need to be made to adapt to the new sized LCD?

Thank you

Regards

Kartik

kartik · ‎2014-04-11

Posted on April 11, 2014 at 22:25

Hi Thierry,

I'm sorry my previous set of question were a little arbitrary. Can you tell me if the Touch panel controller is on board the module from AMP? ie, the AM-640480G5TNQW-T00H supplies the TS3510 on board or is it something that ST designed into LCD board? Because it is not in the BOM.

Thanks

Kartik