Connect 6 TTP223 capacitive sensors to the same input

Good morning,
I am doing a mini project, and I need the following:
Connect 6 capacitive sensors TTP223 to the same input.

I have to get one of these two solutions:

  1. get a single TTP223 to have a larger pulsed area (I have no idea how to do it).

  2. Connect them all to the same D7 input (I have no more free inputs), but when I connect them they don't respond. I understand that it must be because when you have one it sends the 3v voltage and it must cause a problem with the other sensors. I have tried to put a M7 diode, but no matter how I put it... it doesn't work.

Someone could help me please.

Which Arduino are you using ?

You have a typical problem, not enough pins. Look at the PCF8574, it uses I2C and will give you 8 additional I/O. Since you only have one pin, you can remove one and add it to the port expander along with your six TTP223s. If the I2C pins are used as I2C you have it made, if not you can move those two items to the port expander. Some code changes and you are off and running.

If you want to connect the totem-pole output sensor with a Wired-OR, use one schottky diode for each sensor.
The connection the anode to Arduino D7 and the output of the TTP223 to the cathode.
Must be sure to use TTP223 in active-low mode.
And Arduino D7 requires pull-up.

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Thank you very much, I will try that diode, I tried a M7 rectifier diode but it did not cut the current. I think I chose the wrong diode (I don't know much about electronics).

I have also investigated to enlarge the pulsing area by using an aluminum tape area.

When you do the tests I will leave everything here.

The arduino model is not the problem.

If you say so, but a different Arduino could, perhaps, allow a different solution

The forward voltage drop is high, but I think it still works.

Connect as I said and did you switch TTP223 to active low?
You're using a touch sensor module, right?
Many modules require a solder jumper for this.
The default is active high mode.

Hello, in this case the hardware is wemos (lolin) but I have a group of 6 TTP223 sensors and only one input.

I suppose the problem is when I connect more than 1 together I have a voltage problem.

Okay, it looks like I'm going to get lucky and it won't take much craziness.

Basically to be able to use more than one sensor in parallel to the same port and increase the pulsed area, you have to bridge junction A. And use instead of high to low.

And solved, thank your very much people!

I use multiple TTP223 on single GPIO and working fine. Just drive the signal by npn transister.

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