Using ttp223 touch sensor without auto calibration

Hello, i need help with this, i know that the ttp223 has this auto calibration thingy going on where it stops briefly after 7-8 seconds and gets back on.
Is there a way to bypass that? I want it to work as long as my finger is on it and off when not.

If there another borad type or anothe module that is suitable for my application.

Is there a sketch to fix this?

Ps i have a peanut size information on electronics so bare with me, All responses are appreciated.

The idea of my project is like this youthbe video, where when touched stays on until not touched:

Skip to the end of the video(. not trying to recreate this, but the touch concept in a much small case)

Welcome! Save yourself a lot of time and trouble, use mechanical buttons.

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… or IR reflective sensors.

There are quite a few ways to approach this, some will take less time to test than watching that 15 minute video.

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Read the manual, the datasheets to know.

Likely not.

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Beats the purpose of having it touch

I'm not very knowledgeable about all that, i want it to be under a surface like acrylic sheet, im not trying to recreat rhat video, but to understand the concept, they used ttp223 I believe too and many off them and i wonder how they got passed that. I appreciate your response thank you.

The data sheet for the TTP223 says:-

Auto calibration for life
At low power mode the re-calibration period is about 4.0sec normally,
When key detected touch and released touch, the auto re-calibration will be redoing after about 16sec from releasing key

So I don't know why you say:-

Because that is not what the data sheet says happens.

Why not use the MPR121, it has 12 channels of touch sensors, and there is a library for this:- Adafruit_MPR121.h and I believe it only does the calibration on power up.

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I'll look into that, Thank you, but im wondering how in the video the guys did it, they seem to use the same chip thats why, Thanks again i appreciate your response

Not too sure I know what you mean. That is the way I would expect that chip to work, not the way you said it would work.

The video shows them fitting one PCB to each hexagon. So that would be the touch sensor and the LEDs, with some sort of colour control. These look quite big, are you wanting it to be big?

For more information on this chip see:-

And there is a link to the data sheet of this chip at the end of the page.

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Yes i have gone through the datasheet, i have a video cant upload since im new, but i can comfirm around 8ish seconds this time it goes off and back on, i understand its the board and theres nothing much i can do about it, i will order the MPR121 and see if thats my fix. Thanks again.

That 8 second thing seems to defeat the purpose… maybe only when there’s no object sensed, then some time after the last detection,it does the auto calibrate…

Because it’s not clear, buy ONE and test it for what you need.

Is the chip in the low power mode when it does that? It needs to be to comply with what the data sheet says.

I did, i have three im working with, im still having this issue, like Grumpy_mike mentioned ill try using a MPR121 just gotta wait for it to arrive to test it. If you know of any other method to keep it working while touched, and off when not touched would be nice, i want it to work while its hidden under a acrylic. Thank you for your response.

This is my setup, arduino nano, 3 low trigger relays with a 12v led strip

Its not its connected to vcc on the arduino. Heres a video of it and a picture.

Snapchat-2036989421.zip (7.7 MB)

On around 15 seconds on the video is where i kept touching.

What is not?
What boards are you using there? Can you work out the way the chip is wired up?

I dont understand what low power mode is, im assuming 3.3v? If so its not, its hooked up to vcc 5v pin on the arduino nano.
Im following this diagram, but using a 4pin 12v rgb led strip instead of a bulb, in the photo sent earlier I've just used 3 of each, ttp223 and relay module. im a complete beginner i just know the stuff i see on tutorials on this topic bare with me.

Thank you for taking your time to respond, Im thankful.

Does the sketch matter? If so I'll leave it here either way.

int touchPin = A5;// connect output from TTP223 to this
int val = 0; 
int relayPin = 4;// Connected to relay

void setup() {
 Serial.begin(9600);
 pinMode(touchPin, INPUT); 
  pinMode(relayPin, OUTPUT);

}

void loop() {
  digitalWrite(relayPin, HIGH);
  val = digitalRead(touchPin); 
  if(val ==1){
  Serial.println("Touched");
  digitalWrite(relayPin, LOW);
  }
  delay(100);
  Serial.println();
}

Did you read that data sheet from the link I sent you?
Low power is described there.

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Hi,

I have 30 of these chips and I can confirm what ever mode they are in they auto-calibrate after 7-8 seconds. This means that even if your finger is touching after 7-8 seconds it will register that it isn't. I can't quite work out if this is a feature or not. There isn't much information on the web. Some say their chips don't do it other say theirs do. I bought two different batches from two different suppliers with the same results each time.

I got around issue by buying these: AT42QT-1011 link from sparkfun. These work as the datasheet suggests, they stay 'triggered' for as long as something is sensed. They were odd in the fact they worked in my final setting but not very well in test: Link to full explanation:

Probably want to scroll to near the bottom:

https://forum.arduino.cc/t/proximity-sensors-to-switch-on-addressable-leds-in-an-epoxy-table/970815/35

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I've used hundreds of these devices. I also confirm that they 'self calibrate' after 7-8 seconds.
This is great if you use them in 'normal' circumstances - not so great if you want something different!
The data sheets are a puzzle! It seems the auto calibration is disabled on 'certain' devices but I've never encountered a commercial board using such chips. AFAICR this is a package limitation. Only 6 pins on the chip & the calibration switch isn't brought out :frowning:
There are alternatives but they tend to be MUCH more expensive.
I know this doesn't help but you have my sympathy!

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Thank you for your response