Questions tagged [capacitive]
Based on the usage of capacitors, condensators. Alternatively, utilizing the derivative of signals.
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How to make a variable light dimmer circuit without potentiometer?
I was looking at the Wemo dimmer and thought to make one at home myself because the price of it is very high if I buy (including import duty). I searched for the knowledge which helps me create a ...
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Stability - Driving a Capacitive Load
I know I have been asked not to provide video links and ask questions.
But I have no proper guide/mentor or anyone who can provide me better answers other than users in this site. So, please pardon ...
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Capacitive Power Supply Torch
I'm an amateur at electronics circuitry and concepts. I have designed a simple capacitive power supply using few web images and brief lessons. I understand that this type of transformerless power ...
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Qtouch with non-Atmel microcontrollers
Simple question really. Can I use Atmels Qtouch library with non-Atmel MCUs (such as an STM32)?
It seems like Atmel has a solid line of capacitive touch ICs, ...
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Driving Capacitive Load
I did a bistable multivibrator drive NPN mosfet using timer55 and my mosfet drive power LED. Our Load has 3 circuit stage which are emc filter + smps circuit + power Led. I have a problem at that time ...
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How to prevent capacitive discharge on my load after MOSFET off state
I built a button on off latch circuit using nand Gates then connected latched output to Nmosfet's gate with a resistor. My load is a smps circuit drives the power Led and this circuit has emc filter ...
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Strange capacitive soil moisture sensor readings
I am in the process of building an automated irrigation system using capacitive soil moisture sensors and Arduinos.
My challenge comes in with the soil moisture sensors bought from Banggood.com. I ...
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Does this circuit, used to subtract capacitive response, have a specific name (picture in body)?
What I'm doing:
I'm applying voltage pulses to thin films and measuring the resulting current transient, then using these transients to extract the hole mobility.
The problem:
When the films are ...
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How do I trigger capacitive touch screen electronically (without hands)? [duplicate]
I would like to trigger a "touch" or "touches" to a smartphone screen electronically without actually touching the screen with my finger using a remote control somehow.
The idea would be that every ...
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What grounding should I use for this capacitively coupled input?
I'm designing a device that will receive and digitize analog video signals. In analog video, it's recommended to capacitively couple inputs. A typical input might look like this:
In this case the ...
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Headphone Noise from Laptop SMPS
I have been facing an issue that has been a mystery to me for quite some time, and I wanted to see if someone here can potentially give me more insights on this so I can understand why it is happening....
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Does a Microcontroller act as a Capacitive load or resistive?
I'm designing a unity gain buffer (IC MCP6002) and in the datasheet, it says that a small series resistor is required at the output, if the load is capacitive and is >100pF.
The input of the buffer ...
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Why is this camping light deadly?
I am learning, so go easy on me, if you can.
In a video with BigClive, he takes apart a camping light and says it's deadly when you have mains plugged in and usb plugged in at the same time. In that ...
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Loading an Asynchronous Generator
I am doing an experiment that involves loading an asynchronous 50 HZ generator. For the load to consume current it has to be a capacitive load to cause a phase shift between the current and the ...
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Is it possible to drive a capacitive touch screen work as a touch simulator? [duplicate]
I want to simulate a finger touch/move/etc. on capactive touch screen. Obviously using a robot arm and stylus pen is a solution, but it was expansive and the structure was too complex. It would be ...
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Capacitive touch screens and TPU
I'm sorry, I may be slightly out of topic. I'm just an occasionnal "handyman" and I did not found any helping ressource on the web.
I'm willing to protect a touch screen and none of the usual offers ...
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Can transformerless power supplies be UL/CSA certified and is there any specific standard they must meet?
I am trying to bias a linear optocoupler on the AC mains side of a circuit, in order to transfer analog information to the secondary side of the circuit. I have designed the following capacitive power ...
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Simulate capacitive touch
I am using an Arduino Uno and would like to simulate a capacitive tap with zero human contact on my iPhone 5 screen.
What seems to work right now is putting a coin on the screen and connecting the ...
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How to safely switch a big inductive load with a Triac using a capacitor snubber?
I am building a Spot Welder with a big powerful transformer.
I have to switch a big inductive load of 70mH (input of a transformer)
The switching will be done with an SSR (Opto Triac Zero crossing SSR-...
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Real world objects touching reading the same capacitance?
In my project, I am developing a capacitive sensor based system which attempts to identify if two real world objects(*) get in contact with each other. I have done my homework (some) on Capacitive ...
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High pass filter is not resulting as good as the scope's AC coupling
I'm generating sine waves by using a micro-controller and DDS module. The output sine normally swings always positive between 0 to around 1V. But I want to generate a real alternating sine with ...
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Can I make a hole in a touch screen without ruining it?
I need to make a big capacitive touch screen with holes inside it, can this be done without ruining the whole screen?
Thanks in advance.
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How does capacitive sensing relate to the resistance of the object entering the magnetic field? [closed]
Example: Setting up a capacitive area and dropping resistors of different sizes into the field, how do they affect the field differently? Are several resistors accumulative? Would i be able to tell ...
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What touch circuit or sensor to use inside a concrete lamp?
Hi I was planning to build a capacitive touch circuit to control a concrete lamp.
Will the touch work through 8mm thick concrete slab. If yes please suggest best way.
Thanks in advance.
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PIC16F1827 Capacitive Touch Sensor not Incrementing Timer?
So I have a PIC16F1827 on a breadboard and was trying to get a simple demo working where I touch a wire to turn on an LED using the Capacitive Sensing Module. I was primarily going off this example I ...
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variation of thickness of dielectric layer for different textile-based capacitive pressure sensors
For my thesis I am working with textile-based capacitive pressure sensors and I am struggling to see how much variation in thickness of the dielectric layer you can have before you have noticeable ...
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Capacitive coupling: how to collect 60uA from this set-up?
I need to collect at least 60uA via capacitive coupling between a high tension Cu cable with PVC insulation and a connector that is acting as the opposite face of the capacitor (can be a copper plate ...
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Capacitive dropper failure
I have some fridge led light based on basic capacitive dropper. If I connect circuit to AC mains nothing happens. At first I checked all components for mechanical damage and than measured them out of ...
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powersupply ac to ac
I have recently bought a dcp917S and hoped I finally found a wireless chime that I can tie into my apartment buildings bell system. Since I live for rent there I can't do any changes that are not ...
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Help understanding/selecting SMPS to drive capacitive load
I recently bought several SMPS buck converter supplies for a project. They all had about the same specs, typically 90-270VAC input, 12VDC output. Having an expected worst case continuous load of about ...
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Suggestions on conductive materials for textile capacitive pressure sensors
I am doing preliminary research for my thesis. The thesis involves textile capacitive pressure sensors. I am trying to find out more about how the type of conductive material used affects the ...
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Raw data acquisition from a capacitive touch screen
I'm trying to integrate an existing PCAP touch screen into an experimental project I'm working on. For it to work the way I want, I need access to the raw data from the touch-screen nodes instead of ...
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Increase measurement distance of a capacitive proximity sensor - Arduino project
I am working on a 3D tracking interface project that I found online here.
However, instead of using my hand to track, I want to track an aluminum ball with a 2 cm radius, which is connected to ground....
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Capacitive fluid level sensor design and insulation
This is a question regarding the measurement of a fluid level (in my case water) using a capacitive sensor. Capacitive sensors are a common topic, but I have one specific question: It is necessary for ...
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Using capacitive touch switch as guitar pick-up selector
I want to use two Schurter 3-101-401 one for each pick up.
I was able to get them wired up but the signal for the pick-ups comes out no matter what.
Here is the info https://www.mouser.com/...
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Finding the equivelent capacitance of the circuit
Finding the equivelent capacitance of:
simulate this circuit – Schematic created using CircuitLab
I think that it should be:
$$\frac{1}{\frac{1}{C_1}+\frac{1}{C_2}}+\frac{1}{\frac{1}{C_3}+\...
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Shock from Capacitive Coupling
In an AC supply which is not earth grounded, I see a small amount of current flowing to ground from both wires of the supply (live wire has higher) even though the circuit is incomplete.
It is due ...
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Using a straw filled with electrolyte as stylus?
Now what I understand is our human body or a stylus disturbs the electrostatic field of a capacitive screen and thus the mobile calculates the disturbance and does some math and registers a touch.
...
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How do capacitive screens work with rubber head stylus?
Now I kind off know that Capacitive Screens have like capacitors built into them that create an electrostatic field. Now whenever a thing that can carry charge or a conductor touches it distorts the ...
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What is the best oscillator to be used in a capacitive soil moisture sensor?
I am working on this project where I am going to make a soil moisture sensor. The principal that I'm going to use is the change of capacitance of the soil with moisture. What I'm going to do is make a ...
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How can I build a touchpad/trackpad? [closed]
Every laptop has one - a touchpad/trackpad - for controlling the mouse.
I'd like to build my own, external one. I've looked around and I cannot find a tutorial. I have come across 1 example where a ...
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capacitive power supply design query
I was trying to make an LED lamp with 16 series 3528 SMD LED chips. I am planning to use a transformerless capacitive power supply to step down 230V.
As per my calculation 16 led will require the ...
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What material to use for a capacitive sensor?
I'm doing a DIY project that I want to use a capacitive sensor for. I'm having a little plastic box and I want to send a wireless message when someone touches the top of it.
I understand all the ...
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Soil moisture sensor - Interdigital (FEF) vs Coplanar
I am working on the development of a low cost capacitive soil moisture sensor which uses dielectric permittivity changes to estimate moisture.
I found that interdigital capacitor based on FR-4 has ...
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capacitive touch buttons through VERY thick glass or macrolon? [closed]
for a science-project I need to create 4-5 capacitive touch buttons through thick glass or macrolon. I think we talk about 15cm atleast, if not 20. I wonder if a big coil or big sheet of tinfoil would ...
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AT42QT2160 capacitive touch controller inverted Cs voltage - no touch detected
I'm trying to make my own development board for the AT42QT2160 Touch controller, since the original one was discontinued. I've designed the PCB with 8 buttons and a slider consisting of 8 sections. It'...
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Noise due to stray voltages in a data acquisition system
A single ended earth grounded data-acq. board on the left in the below illustration has inputs coupled by BNC cables coming from force transducer amplifiers A1, A2, A3, A4 as shown on the right:
If ...
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2D DIY capacitive panel
I'm planning on replacing lights with smart bulbs (e.g. Yeelight RGBW) and replacing light switches with capacitive panels connected to Arduinos which will send data to RPi, which will then control ...
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HF signal in a null experiment. What is the exact mechanism?
Since I've tried to experiment with electronics, I am faced with the problem of HF noise and signals bypassing almost anything I try to stop them. This begun with my attempts to filter the noise of a ...
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Current limitation to capacitive voltage divider
For an AC capacitive voltage divider, I would think the amount of current that could come from the divider would be limited by the absolute size of the capacitors. The flow of current should be a ...
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