Questions tagged [capacitive]
Based on the usage of capacitors, condensators. Alternatively, utilizing the derivative of signals.
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Looking for a transparent conductive spray/paint/ink
I know there are conductive sprays available, but these are strongly coloured due to the metals inside them. I am trying to make a (dry) wooden surface capacitive, but would like to have the feel and ...
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Split-phase 230VAC transformerless capacitive power supply for 5V@30mA regulated output -- series cap?
I'm a hobbyist developing a hybrid power switch (electromagnetic + solid state) for a resistive electric stove (8kW max) top. I have a profoundly autistic, disabled adult in the house and I need a ...
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Grounding Plexiglass
I have a sheet of plexiglass that has metal strips (Aluminum) that will be connected through wires to an Arduino. The Arduino is grounded but the metal strips are not. The metal strips will rest on ...
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Capacitive AC voltage detection
As I understand it, a non-contact voltage tester works by creating a capacitive connection from a power line to ground, via the detection circuit and the operator's hand/body. This connection passes a ...
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Capacitive sensor circuit
I'm designing a capacitive proximity sensor for detection of human presence. My requirement is that I should be able to detect presence by monitoring change in capacitance at the highest possible ...
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Transistor selection for 5V LED circuit
I'm having a trouble selecting the proper transistor to switch this LED circuit
simulate this circuit – Schematic created using CircuitLab
The LEDs are 3.6v at 20 mA.
I tried figuring the ...
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ESD protection of capacitive touch doorknob circuit?
This is a follow-up to my question: How can I use a generic doorknob as a capacitive touch sensor?
I am now ready to move beyond the proof-of-concept stage, but I have not yet learned of a ...
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Glitchy Touchscreen Caused by Charger [closed]
I recently bought a Nexus 4. I had a couple of spare chargers laying around. I used a charger that apparently had an issue exactly like: https://www.youtube.com/watch?v=mrpBTG0a6K8. If I used my own ...
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What are those black things on the board?
I'm a beginner in electronics, and I'm ignorant of many basic things.
Check out these black things on the board:
These are from a keyboard.
I'm disassembling it and I want to connect my own ...
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Water level: BIG capacitive level sensor with steel bars?
So I want to measure water level under a bridge, or inside the city drain.
Would it be possible to run two long (4 meter) metal probes, each one enclosed inside a PVC pipe, and placed one next to the ...
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Simplest touch sensor for a copper surface
I'm looking for the simplest way to implement a binary on|off touch switch using a single pole. The touch surface is copper. The position or pressure of the touch is not needed, just simply:
On = ...
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Designing a Transformerless power supply
I am working on a transformerless PSU for maiking a 3nos.x3 watt led, each having forward voltage around 3.6v and current around 650-700ma.
I have worked on this kind of circuit:
I guess a 1uf ...
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How to use a capacitive touch screen without a human hand
I'm a programmer, and I usually hang out over on stack overflow, but I have a electricity question.
I'm trying to interact with an APP on my phone by indirectly touching the the screen. Modern ...
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Replacement IC for the touch-button QT1081?
A project I'm working on needs several touch buttons. I found the datasheet for the Atmel QT1081, which supports up to 8 capacitive buttons, with the added advantage for our circuit that there are ...
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Thermoplastic-based touch panels: why not?
(I'm new to EE.SE, so I don't know if this is on-topic here. Please forgive me.)
From what I understand, capacitive touch technology relies on coating one side of a resistive material with a ...
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How to drive and control capacitive load?
There is electrochromic film (which is some kind of capacitive load) that need to be driven with 50Hz alternating current, load voltage should be controlled in range 0-100V (with 8 or more fixed ...
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Driving LM3886 at 100 KHZ in Bridge Tied Load (BTL) configuration?
Would someone have experience with driving a pair of LM3886 Overture Power Amplifiers in BTL with up to 100 KHz sine wave?
My parameters:
Frequency band of interest: 20KHz to 100 KHz, sine wave
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Capacitive touchscreen [duplicate]
I am doing project in which I want to perform read and write operation by using a capacitive touchscreen. What I know is I can trigger capacitive touch screen by:
By using electromagnet as I heard ...
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Is there a 10X probe compensator BNC, but with out the probe?
Is there such thing as a compensation BNC like the ones found on 10X probes? I'm basically taking about a BNC coupler with a resistor and a adjustable cap in it. I guess it would be like a standard ...
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Formulas for Integral Components
Formulas for Integral Components:
I am looking for "simple" approximative formulas for integral components. In particular for:
A grounded interdigital capacitor (i.e. above a ground plane and with ...
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Smallest touch that can be detected on smartphone touchscreens
Not sure if this is the right place to ask this question, but what is the smallest touch (in terms of height and width) that can be detected on most smartphone screens (capacitive touchscreens found ...
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Is FR4 waterproof? What about soldermask?
I'm investigating ways of making a capacitive sensor that will operate in very moist environments, potentially even submerged. What I need is a way to make some conductive plates in a specific ...
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Conducting plastic for capacitive touchscreens
As I am disabled I have to use a headstick (see picture below) to do stuff on the computer. I also have a phone with a resistive touchscreen, which works well with my headstick.
But here is the ...
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Triggering a capacitive sensor electronically?
I'm working on a little project I call my "Green Box". Basically, I'm trying to drop my electric usage as low as possible, without losing the convenience of my gadgetry.
So far, I'm incorporating a ...
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PCB Matrix Touchpad?
Is it possible to DIY your own capacitative touchpad on a PCB? The last page of this mentions it:
http://www.ebv.com/fileadmin/products/Products/Fujitsu/FMA1127/...
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Can a water drop do a "fake" touch on a capacitive touchscreen?
If a capacitive touchscreen is hit by water drops, like rain, will it report a touch?
I'm trying to evaluate what is the most appropriate touchscreen solution to use in an outdoor kiosk.
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Capacitive Touchscreen for DIY usage?
Anyone know of a good source for capacitive touchscreens in low quantity at a reasonable price? Just something to play around with in projects, I'm interested in either small (eg for portable ...
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Capacitive Sensing
Is there a way that I can make an Arduino or other Micro-controller detect a change in capacitance?
I'm thinking of having a screen on my door that only turns on when you touch the metal door handle.
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