Questions tagged [touch]
The touch tag has no usage guidance.
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Need advice on tapping into touch screen connected to LCD
I'm hoping to get some advice on a technical issue I'm currently facing. I am attempting to tap into a touch screen that is connected to an LCD, but I'm feeling a bit confused about how to proceed. ...
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Can the pitch of an electrode, of a capacitive sensor (PCAD) be greater than 10mm, say 14mm?
I'm looking for a PCAP sensor (projective capacitance), which seems to be made by all manufacturers as a diamond mesh similar to the image below:
The pitch as the image above shows appears to be a ...
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Is there a single cycle wave trigger circuit?
Is there a circuit design where if the input is high (at any length of time), the output will only be one cycle at a fix amount of time?
I'm currently working on a capacitive touch switch (I'll use ...
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Using skin to close low-voltage circuit
I am trying to create a ping pong ball sized light-up ball that should light up when held in my hand, as in the 80's toy inspired by the movie/television series "Star man".
The circuit must ...
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Electrical noise between dimmer circuit and halogen transformer output
I am currently building an ESP32-based dimmer control for halogen transformers.
The dimmer should be controlled by touching any part of the transformer output circuit. Thus, I somehow need to connect ...
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Resistive finger PCB button
I want to do something similar to this question:
PCB "Touch" Button
However there the PCB was not described that much. I have a design where each 'finger' is 1mm apart.
And I'm not sure ...
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LED driver circuit works only when I touch it with my finger
I'm trying to convert an E14 RGB LED bulb to be able to power it from a lithium battery. Inside the bulb are 2 PCBs - a transformer and a LED driver - which are connected by 3 wires. Black and red are ...
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Odd 4x3 touch keypad performance using TTP229
I designed a 4x3 keypad using a TTP229-BSF and an ESP32. The board works perfectly when I put 4 mm plastic over the board.
But when I add 2.5 mm of plexiglass over the plastic, some of the keys (3, 6, ...
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I need help building a low-cost contactless water sensor
I tried to build a contactless water sensor with some touch ICs, but all of them use auto calibration features i.e. they can sense the presence of water without contact but after some seconds, they ...
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How can I use a microcontroller to trigger an existing capacitive-touch pad?
(Note: I have found several other questions on a similar topic, but none of them address my specific issue.)
I have a lamp that is controlled by non-contact touch buttons. The user-facing surface is ...
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Problem with TTP229-BSF using Arduino Uno
I'm trying to use a 16-channel capacitive touch sensor named TTP229-BSF with an Arduino Uno. I use the following code it works correctly when i touch directly but when i place two 4 mm plexiglass pads ...
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Bypass touch sensor IC with a button?
I want to replace a capacitive touch sensor on a circuit board (I think it’s a TTP223) with a tactile switch to overcome over/under sensitivity issues. I have wired a switch to ground and the CMOS ...
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What is the best way to achieve triggering a function on device contact?
Let's say I have a smart pen. It has a microcontroller that can communicate with my server. I want to have a really small and flat gadget (let's call it The Receiver) that when you touch it with that ...
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Discrete resistive touch sensing circuit not being able to be detected by animals [closed]
Looking to build a conductive matt that is split in two with a insulator in between them to allow detection of when a dog or cat walks over it and completes the circuit through their body, but as both ...
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How to trigger cap touch sensor without touching it?
I have a device that has metal spring connected to microcontroller pin that has in-built cap touch sensing . This spring is used to turn the device on and off. I plan to place the device in ...
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Relay is switching by touching optocoupler with finger
To switch a 12V relay with a micro controller, I designed ("borrowed") this schematic.
Build the pcb and it works great. But there's a little bug that got me a bit worried. If I touch the ...
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How to setup a GT911 touch panel using Arduino? (I2C communication)
I have a 9 inch touch panel which has a GT911 controller and works with I2C. I should configure its registers and then read the touched points' coordinates. It has 6 pins (Vcc, GNd, INT, RST, SCA, SDA)...
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Any glaring mistakes in I2C touch & OLED PCB design?
Would greatly appreciate any expertise/suggestions on solving this problem! In particular have I done anything glaringly stupid when it comes to my PCB design??
I'm trying to get touch control ...
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Issue with a touch switch
I made a touch switch in PCB based in the following schematic
When touching the plate with a finger the BJT turns on and the 555 trigger pin goes LOW activating the pin 3 (OUTPUT).
The time the ...
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ESP32 - Touch sensors with 1 meter wires
I am trying to use the Touch sensitive pins of a ESP32. Problem is that between the ESP32 and the actual touch pads there is 1 meter of wire. without the cable attached the value is > 200, but as ...
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Touch pad Document
I tear down one touch pad and wonder what technology they used.
I am sharing picture of it.
Any one know what is used for touch sense ? (my guess is capacitive).
I am planning to design one by myself. ...
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Touch switch for hanging lamp (touching metal bar): Ideas?
A few years ago, we have bought an IKEA Glimt hanging lamp that operates with halogen lamps. It has a "touch dim" functionality, so when a person touches the metal bar of the lamp, it dims (...
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Touch sensor selection
I am currently researching a touch/force sensor for my project. Purpose of this post is to get your help in sensor selection.
Below is the information about the project so that you can get insight ...
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Simulate capacitive touch sensitivity and noise immunity
Due to covid, we are limited in the time we can tune our touch designs before EMC tests.
The device we are using has a PC based analyzer that is connected to the device over a serial protocol. ...
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Capacitive Touch Faucet Solenoid Battery Box vs AC/DC adapter [closed]
I have a MSTJRY touch kitchen faucet purchased through Amazon. It uses a valve solenoid in line with the water supply to control the on/off of the faucet based on capacitive touch on the faucet stem. ...
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RaspberryPi touch sensor using transistor
I built the following circuit. When I touch the rogue transistor base wire and GPIO is outputting, the LED lights up (still not quite sure why, so if someone could explain this, that'd be helpful, too....
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Capacitive touch sense problem with battery powered laptop
I designed a PCB that includes capacitive touch. The circuit works with 5V powered from USB.
When Laptop is connected to 220V line, the PIC can sense capacitance variation.
When Laptop is not ...
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Use Mosfet as a touch switch
I would like to use N-channel as a touch switch which will be an input to the microcontroller. Currenty I am concerning about power draw. The whole device will be in metal case and I am planing to ...
user208862
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Bypass touch switch on humidifier circuit board
i have a simple humidifier that only powers on by a touch sensitive switch.
I need to bypass it because when the power is off after that the device doesnt start automatically.
I tried some things but ...
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What is the best way to sense if a climbing hold is being used by a climber?
I am designing a climbing wall game that gets what holds are being used as inputs. I'm currently planning on using a Kinect sensor to tell where hands are relative to holds and capacitive touch ...
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Multiple ESP8266-12E's with multiple touch sensors
I'm looking for some advice, and I'm not sure I'm barking up the right tree by using ESP8266 NodeMCU CP2102 ESP-12E's.
I am currently using Arduino IDE to program the 8266's. I have two 8266's that I ...
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Can a capacitative touch switch provide multiple response levels?
After recently discovering the ESP32, I've been inspired to attempt my first electronics project. It will be a very simple wifi-enabled light.
I thought I would take advantage of the capacitative ...
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What is this glassy black bulge on a keytar button chip? [duplicate]
I'm disassembling a non-functioning toy keytar. This is the chip behind a couple buttons, including an on/off button. What could the black, glassy bulge component be?
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Trying to identify a component in a 12 volt LED on/off touch switch
I'm wondering if anyone can help me identify what this 8 pin IC is, in a capacitive on/off touch switch I have. It is a soic or 8-VSSOP package. 64RX-Y is written on the bottom of the IC, nothing on ...
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What type of touch button is this?
There's a touch button which has a spring on the PCB.
Is it capacitive?
How does it work?
Do I need a special circuit to read touch events?
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ESP32 touch sensor outputs unstable values
I am trying to implement touch functionality of esp32 development board to toggle a led. But on uploading a simple touch detection sketch, output have spikes i.e. usually value remains near 100 but ...
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Waterproof capacitive touch-sensor issue
my goal is to develop a waterproof capacitive touch-sensor.
In many sources on the internet, it is said that a mutual-capacitance sensor can achieve this.
For example, in the TI Designs: TIDM-1021 ...
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Power ON-OFF Memory Logic Circuit
There is touch sense circuit that controls a SMPS circuit drives a power LED at output. When disconnect the energy while LED ON, if I reconnect the energy LED must start be as ON state. I need a ...
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Question Regarding Capacitive Sensor IC
I have this Capacitive Sensor IC
I am trying to understand and analyze how to use this IC.
In the datasheet, on page 13 - Function description, it is mentioned as "There are four selectable non-...
user220456
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Question about capacitive sensor designs with direct touch to copper or aluminum
I've seen some DIY capacitive touch sensor projects where the sensors themselves are strips of aluminum or copper soldered to a non-grounded wire, where the user touches these strips directly with ...
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Finger touch signal detection with microcontroller
I use darlington transistor for detection of touching. Finger or hand touch to BASE, only make about 0.8-0.9V voltage on the EMITTER side. How can i increase this voltage level to 3V for detecting ...
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Understanding Touch Switch with BJTs and Relay
We worked on this circuit today in one of my labs and it had my groupmates and I puzzled. We had a 1k resistor in series with an LED on the NO side of the relay.
I searched for the circuit online and ...
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How do I read a simple touch sensor value from Arduino? [closed]
I suppose instead of connecting to the LED it will connect to A3 on the Arduino for example but I'm having a hard time making it work.
I don't know which point on the circuit should be connected to ...
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Touch IC TTP223 hangs at 5V after working
I used a TTP223 IC operating on 5 V. I use the touch IC output (when high) to turn on the LED and (when low) to dim the LED. The LED is operated by the external 5 V. It uses only the touch IC output ...
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