Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [touch]

47 questions
2
votes
1 answer

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 plastic with icons printed on it. When the user…
Sod Almighty
  • 1,295
  • 13
  • 22
1
vote
1 answer

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 CTS as an abbreviation) using the CMOS 4000 series…
Igcasan
  • 11
  • 2
1
vote
1 answer

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 be powered by a coin battery cell, preferable a 1.5 V…
Erik
  • 11
  • 2
1
vote
1 answer

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, and 9) become less sensitive than the others and…
salar1991
  • 99
  • 8
1
vote
1 answer

Discrete resistive touch sensing circuit not being able to be detected by animals

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 can avoid things that they can sense and don't…
user66001
  • 115
  • 6
1
vote
2 answers

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). You can find the link to the datasheet and the…
Mohammad Ebadi
  • 11
  • 4
1
vote
1 answer

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 (or when touching for a short time, it switches…
sophonet
  • 11
  • 1
1
vote
1 answer

Capacitive Touch Faucet Solenoid Battery Box vs AC/DC adapter

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. There is one black wire that connects the…
mjhuffer
  • 13
  • 2
1
vote
1 answer

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 touch pins on the ESP32 and add two on-device touch…
Andy Harvey
  • 121
  • 2
1
vote
1 answer

What is this glassy black bulge on a keytar button chip?

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?
Anna
  • 785
  • 1
  • 10
  • 22
1
vote
4 answers

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 falls to around 30 randomly for no reason. This…
Rishabh
  • 143
  • 1
  • 10
1
vote
0 answers

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 Liquid Tolerant Capacitive Touch Keypad Design…
Wheatley
  • 670
  • 1
  • 6
  • 12
1
vote
1 answer

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-harmonic sensor frequencies for generating the sensor…
user220456
1
vote
1 answer

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 their finger to be sensed. I'm a bit unclear as to…
Nick Nagy
  • 85
  • 1
  • 7
1
vote
1 answer

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 found this website explaining, but his…
ModularMan
  • 541
  • 1
  • 5
  • 10
1
2 3 4