Questions tagged [capacitive]
Based on the usage of capacitors, condensators. Alternatively, utilizing the derivative of signals.
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Wiring RGB Vandal Switch as PC Power Button
I'm trying to wire up a Schurter CPS16 capacitive, multicolour (RGB), anti-vandal switch to my PC for use as a power button.
The switch function is momentary and normally-open.
Tech Sheet
I'm just ...
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Reliable way of measuring mains voltage by capacitive coupling with oscilloscope
The question is not about any precise measurements, just for the lack of a better title.
Trying to model what one of those non-contact voltage detectors would see when brought closer to a live wire.
...
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AC mains wire finder + live wire equivalent circuit [duplicate]
I'm talking about devices for tracing hidden AC mains wires in walls like this one: https://www.ebay.com/itm/3-in-1-LCD-Wall-Detector-Stud-Center-Finder-AC-Live-Wire-Metal-Detector-Scanner-/...
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What is the chip used in CJMCU 0401 Capacitive Touch sensor?
I'm trying to make my own PCB with touch keys. I've used the CJMCU 0401 capacitive touch sensor module and now I want to use it in my project. On the chip that is used in this module, there is only a ...
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Using a TPP223 capacitive board instead of a mechanical button
I have this CSR8645 bluetooth module and I wanted to use TPP223 capacitive buttons for its inputs - vol+, vol-, next, prev, etc., but I am wondering if it will work at all.
The CSR8645 is originally ...
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capacitive reactance in a stranded wire
Can a stranded wire exhibit a capacitive reactance?
I measured the real and imaginary part of a piece stranded wire using an old LRC meter( HP 4284a).
Applied an open loop and a closed loop ...
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Capacitive sensor as drop-in replacement for mechanical button
I have a device X (talking toy), which has a jack of two wires for an external button. That is, I can short the two wires and device X accepts it as a press of a button.
Now, I want to use device X ...
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ATtiny13a capacitive power supply
I would like to power my Attiny13a MCU with a transformerless capacitive power supply. The MCU itself needs only a few milli amps and it will drive 2 LEDs at 15mA each through it's digital pins. So I ...
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Figuring out the protocol of an SPI device without a datasheet
I am pondering about interfacing with the iPad Mini 2 touch panel. It seems that no one has successfully done this and/or published anything about it, so I want to take a stab at it.
As far as I ...
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Capacitance on the output of an op amp
I have read a lot about capacitive loads on the output of an op-amp and the possibility of unwanted oscillations and instability. my knowledge on phase margin and frequency domain analysis is a little ...
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Modelling a "scope probes' acting as an antenna" phenomenon in a circuit
Here below I draw a simplistic model for stray capacitance issue in SMPSs:
Basically pF level Y capacitor across the AC line forms an RC voltage divider when measured by a voltmeter with respect to ...
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How can I fool an auto-calibrating capacitive touch sensor?
I have a MicroBot Push - looks like this:
Below the blue ring on the top is a capacitive touch pad and a TTP223-BA6 controller. Here's what it looks like under the hood.
It's a long story, but I ...
user29392
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capacitive sensing PCB overlay
reading some of the capacitive sensing IC datasheets around, they always recommend an isolation overlay over the sensor pad.
Like this:
I'm wondering, why not use the actual PCB as overlay?
like ...
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Design of capacitive proximity sensor
I am currently designing a microgripper for which I need a proximity/distance sensor.
Please refer to the image below for design requirements.
Due to the force application (as shown in the image), ...
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Capacitive touch screen sensitivity question
I have a question about capacitive touch sensing. I have read a few related questions already (here, here and here) and I think I understand the basics.
From my understanding, when a human uses a ...
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Is it a disadvantage for a generator to supply both resistive and reactive current to its load?
Suppose
The power network 1 has a resistive load and therefore the current supplied by the generator 1 to the load is purely resistive.
The power network 2 has a resistive + inductive load and ...
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Rugged Capacitive Single Touch Screen
I am looking to make a capacitive single touch screen into a small table. Which I can use to put coffee cup etc on. It does not have to be waterproof but rugged enough to not scratch over time easily ...
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Marvell PHY to KS8999 PHY connection
I'm trying to design a custom board with Marvell 88E1111 PHY and I want to connect this board to another board with KS8999 PHY on it. I want to connect two phy sides with capacitive coupling.
The ...
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Peak value of sine wave for capacitively coupled inverting amplifier
I was working on question 2.23(a) and there is asked what input voltage is needed in order to ensure that the output does not clip. The clipping limits are +10 to -10 V.
I solved that, and, ...
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Digital control over capacitive touch
I would like to generate computer controlled touches on a capacitive touch screen (e.g. iphone) using the following setup: I have a conductive patch (size of finger) that I place on the touchscreen ...
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Capacitive projectile triggering touch screen
I've read through a number of questions (How can a capacitive touch screen be triggered without human contact?), (How to use a capacitive touch screen without a human hand), (What is the minimal ...
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PCB stackup for capacitive buttons, LEDs and other components
The design I am working on has about 30 capacitive buttons, LEDs for back-lighting, about 8-10 ICs (capsense controllers, LED drivers, MCU, etc), many passive components and coin cell batteries.
I am ...
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Capacitive proximity sensor size?
I want to design a capacitive proximity sensor to detect human presence at a distance of 10-15 cm.
Now I made my research on this type of sensor but everything that i found doesn't tell me about the ...
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Why power factor correction for Capacitive load is more difficult?
When we want to correction power factor of a motor(inductive load) its simply can done by adding an capacitor in parallel with the motor but its not possible to correction power factor of an ...
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Eliminating ghost voltage and breaking ground loops in a system
The above illustration is a setup I use where amplifier outputs go to a data acquisition system through BNC cables. The data acquisition system is earth-grounded. Mains system voltage Line to Neutral ...
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Capacitive sensor - How to activate with a portable device
I'd like to activate a capacitive sensor - a smartphone touch screen for instance - with an electronic device - say an Arduino board. Basically I'd like to reproduce this instructable, but with one ...
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Capacitive sensing with large distance
I am curious on how capacitive sensing work. How does it sense hand gesture, or measure water level when the distance between the capacitance plates are large (5-10cm)?
I thought that capacitance ...
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Differential CVD waveform in PIC18F45K50
I am using PIC18f45K50 for capacitive touch button using a differential CVD (Capacitive Voltage Divider).
My capacitive button works. However I am not able to get the standard differential CVD ...
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Wall touch switch design
How can I make a capacitive wall touch switch? remembering that the wall standard light switch has just two wires for close the circuit. How can I supply my circuit when the light is on in order to ...
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How does the glass screen of smart phones not block the discharge of capacitors in capacitive touch screens?
Glass is one of the best insulators when designing high voltage electronics, and correct me if I'm wrong, but capacitive touch screens work by measuring the charge of capacitors in a grid on the ...
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How do I find C & L from XC and XL?
Calculating Capacitance and Inductance from Capacitive Reactance and Inductive Reactance
I'm trying to find the inductor (L) and capacitor (C) values using the inductive reactance (XL) and capacitive ...
user126396
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Relay contact sticking while driving a capacitive load
I am using a Panasonic relay (ALQ105) rated for a resistive load of 10 amps 5A at 250V to drive LED bulbs. These LEDs have capacitive circuits in their ballasts and hence draw high inrush current when ...
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Is electric field of capacitive sensing circuit harmful and is it radiation?
I have constructed a circuit for capacitive sensing. The code charges and discharges a conductive plate. This uses an Arduino which is connected to a computer via USB.
I have decided to measure the ...
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Capacitive touch sensor design
I made a PCB with several capacitive pads to be read by IQS127.
They work, but any material I put close to the PCB surface will trigger the output, even the 8 mm glass I'm going to use.
The pads ...
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capacitive touch film or integerated capacitive touch panel display? using under glass [closed]
We need to put display under 2mm glass. Our device must have capacitive touch input.
which method should we use? Capacitive Touch Films (place it under glass) or LCDs with integrated capacitive touch (...
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PCB trace capacitance
I am designing a capacitive touch keypad using cypress MBR series. The design guide has an excel spreadsheet to help with max trace length and button dia requirements. The idea is to keep the button + ...
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Electrically simulate and toggle a capacitive touch
I am interested in testing a capacitive touch device for reliability by simulating touch events periodically.
I would like to do this purely electrically if possible (no mechanical parts), or with a ...
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Sensing the capacitance value of a material - for an ID system
This is a follow up question to 'How does a Capacitive ID / Signatures / Sensing system work? e.g. Google Bloks'
In the 'Google Bloks' project. A tangible programming experience is created by ...
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How does a Capacitive ID / Signatures / Sensing system work? e.g. Google Bloks
In the 'Google Bloks' project. A tangible programming experience is created by allowing children to place physical instruction blocks next to each other.
The computer is able to read the sequence ...
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Elegant non-mechanical way to switch on battery-powered device the first time
For a primary-battery powered device, that will be stored for a period of time before first use, what is the most elegant non-mechanical* way to switch it on for the first time, after which it will ...
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Minimizing capacitive crosstalk in open collector quadrature speed sensor
I am integrating a speed sensor (Honeywell SNDH-T4L-G01) which comprises 4 lines: VDD, VSS, A, B. The last two signals provide speed and direction information in a quadrature format.
These are open ...
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Water level capacitive probe topology
I'm building a small capacitive water level sensor for a reservoir (16cm tall x 10cm x 7cm).
This prototype gives me 10pF on free air and 20~30pF on medium water levels, so its definetively doable (...
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Capacitive Coupling Between Adjacent Conductors
I have been unable to find a definitive answer to my questions after some extensive browsing online.
My question involves the coupling between two adjacent conductors (wires, PCB traces, etc) due to ...
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Heartrate measuring using capacitive touch sensor
I am new here, and I hope someone could help me.
So I've read in the datasheet of the capacitive touch sensor ATMEL42QT1011
that we could use it as a heart rate sensor.But what I don't understand is ...
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Simple short range object proximity identification using capacitive sensing
I'm designign a device capable to sense proximity with other identintical devices and communicate that to a central node via bluetooth. The problem I'm trying to solve is showed in figure.
So far I ...
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Homemade shielding of a wire to a capacitive sensor
I'm using a capacitive sensor CAP1188 with Arduino, connecting 8 of its touch sensor inputs to 8 copper boards that I want to be the actual touch surfaces.
The wires to the sensor are quite long (100 ...
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Capacitive touch switches drop voltage and limits current
Bought two different touch switches/devices to toggle outputs to other devices. I use this on USB power so input is 5V. With use of a powerpack it can handle 2A max.
NOTICE: Ask my question here ...
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capacitive switch behind a mirror (silver backing)
I am new to this field, and I would like to DIY a mirror with a hidden capacitive \inductive touch sensor behind it, once touched it will turn on a 12V LED light.
I have bought a capacitive switch ...
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Grid is capacitive in the evening
what does this term mean? "the grid in the evening is capacitive"?
I work at a company and we are working on integrating a battery storage system on a utility scale for peak shaving of solar. When we ...
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How to obtain the transfer function of the capacitive sensor?
I want to obtain the transfer function of this capacitive sensor which in the circuit, C is the variable capacitor that transforms displacement to electrical signal and E is the dc voltage source ...
