Questions tagged [capacitive]
Based on the usage of capacitors, condensators. Alternatively, utilizing the derivative of signals.
58 questions with no upvoted or accepted answers
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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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High-side mosfet switch placement
this is a power circuit I'm trying to complete:
the button at top turns the curcuit on, supplying VCC to mcu, and the MCU will output a high signal to a pin (marked in pink) which turns the N-MOSFET ...
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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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Current slew rate specification of op-amps?
I know that slew rate specifies how fast the output voltage of an op-amp can change. But is there a measure that specifies how fast the output current of op-amps can change?
I need this information ...
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Differences in capacitive loads
I'm in school and I am trying to figure out a question for homework. It reads as stated:
Version
Voltage
Clock Rate
i.
Version 1
1.75V
1.5 GHz
Version 2
1.2V
2 GHz
ii.
Version 1
1.1V
3 GHz
...
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Capacitive Touch Pad Design with TTP224 ic
I am designing circular capacitive touch pads of Dia:20mm driving from TTP224 IC on my PCB. There will be 2mm glass panel above Touch pads. My PCB contains other circuits like Arduino, Antenna bands ...
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How to read out a capacitive sensor, (CDC, CVC, TDC)?
What are the main principles for reading out a capacitive sensor? I read a lot, but I cant figure out what re the different options.
I think that an option is to convert the capacitance into a ...
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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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Convert capacitive sensor into physical button?
Is it possible to turn a capacitive button in to a protruding mechanical one?
I am thinking something round that sticks to a surface with a capacitive button on it and is essentially just a button ...
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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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What CAD software is used to design and manufacture projected capacitive touchscreens?
I am looking to learn more about how projected capacitive (PCAP) touchscreens are designed and made, specifically with laser ablation. What kind of CAD software is used to create layered drawings for ...
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Correct design of capsense controls
I am trying to design a PCB with some capacitive controls. My first iteration did not seem to work well:
This was a 2-layer 1.6mm board with one circular control, and 5 buttons. The board is 48mm ...
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Grove capacitive fingerprint sensor not working
I have just purchased one grove capacitive finger print sensor.
link.
I am using Arduino Nano and followed there tutorial but the example code isn’t working.
Blue light on sensor never turn to green ...
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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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Is there definitive documentation regarding the reliability of a capacitive touchscreen?
I'm working with a manufacturer who wants to use a touchscreen (like a mobile phone) to activate the machinery but is afraid the touchscreen could give a false reading.
This would be a touch-and-hold ...
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Bypassing Capacitive Touch Sensor on Wemo Insight
I have a WeMo Insight plug that I'd like to use to monitor the power consumption of my networking devices but unfortunately if the power goes out, the WeMo device will not come back on automatically. ...
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Ground mesh under the capacitive touch pad
I am going replicate a circuit basing from adafruit AT42QT10xx, I will be using the AT42QT1010 variant.
The touch pad is the blue pad bottom layer, but there is this mesh on the top layer after i ...
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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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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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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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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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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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Capacitive where is the touch?
I am a newbie in the world of circuits and electronics. But we all started somewhere.
I have this idea about a street sign that should be used as an instrument. All most like a Theremin. Touching it ...
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Can I use a capacitive sensor to detect a person proximity without touch?
I only see uses of capacitive sensor to detect touch. But I wonder if I can calibrate a capacitive sensor to detect if a person is close enough, even if the person is not touching it.
I intend to use ...
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MOSFET SSR inrush current with capacitive load
I'm searching for a small switch to switch 400 V AC 50 Hz on 11 nF capacitive load. Switch would not be opened and closed often and continuous current would be under 2 mA. 2 resistors were added ...
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Circuit To Simulate Capacitive Touch Button Press - Raspberry Pi Zero
I realise similar questions have been asked in the past about automating capacitive touches, but I'm aiming to put this into practise with a simple circuit.
I want to be able to simulate / automate ...
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How can I make an effective head-mounted pointing device for a touchscreen
I have read How can a capacitive touch screen be triggered without human contact? and feel a bit closer to understanding the technology, but I am still a bit puzzled.
I recently picked up the task of ...
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How to simulate a finger touch electrically to remove noise
I am working on a project with "SIM800L" GSM module, the problem is that there is a noise from the module in the calls and it disappears when I touch the module's body with my hand.
Kindly, ...
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High voltage pad buffer design with 2nF load and ringing on first stage output
I am trying to design a high voltage (12V) buffer that will drive a sine wave with rail-to-rail peak-to-peak amplitude and a big capacitive load, maybe 3nF.
Browsing I came upon this Master's project: ...
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How to remotely control a TT6061A dimmer using an ESP8266 and detect its current state?
I am trying to remotely control a TT6061A (embedded inside an existing module), 3-way dimmer using an ESP8266. My goal is to set the device state to OFF, LOW, MEDIUM, or HIGH.
However, there is no ...
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Ultra-fast load switch
I have a question that I am assuming has a very easy answer (hopefully). I am trying to turn on and off the power to a pcb really fast, on the order of 1us. My problem is that my board has some bypass ...
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Using capacitive touch screen without human hand
I'm trying to learn more about how to engage a capacitive touchscreen without using a human finger. Full disclaimer I'm in mechanical engineering (notoriously known to have difficulty comprehending ...
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People detection in large rooms using antennas
After coming across a 2004 installation by Carsten Nicolai titled "anti" where he used a theremin as an element for presence sensing, I was wondering if this principle could be extended to ...
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Capacitive load in inverter
I'm trying to understand the effect of a capacitive load at the output of an inverter.
And how does it affect the output signal when this capacitive load is high and when it is low?
Could anybody ...
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Soft-start design and performant with short-circuit test
I am working on a soft-start for a capacitive load. I using module QSB40024S24 to create 24V output. At first, I allowed the output of the module to connect directly to a capacitor array (21.4mF in ...
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Capacitive touch sensor senses every materials touch
I have a ttp223 capacitive touch sensor. It has three pins, VCC GND and I/O. I left I/O open for test purposes. I connected the VCC to 5V and GND to ground. When I touch the sensor, its led indicator ...
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TTP223 capacitive sensor on USB switch takes two presses to work
I'm trying to solder a TTP223 capacitive touch sensor to a USB switch (specifically a "UGREEN USB 3.0 Switch, 2 In 4 Output") to rig a sort of capacitive KVM switch to a desk PC I'm building,...
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Variac and Other dropper in line
I have a beautiful old variac, with a sliding (rotating) center contact.
I would love to use this on a nice LED string inside a glass bulb on top of the device.
But also, use the variac as the dimmer, ...
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Distribution of charges in an electrostatic study
I have a question concerning the capacitive coupling between two conductors. The capacitance C between the two is only a function of the diameter of the 2 studied conductors, the insulation thickness ...
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how can I simulate the MMA7361L?
I wanted to know if there is a simulator that could include the model of the capcitive accelerometer NXP MMA7361L, and if there is a tool-box in matlab that could include it or should I find the ...
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Where is the capacitive coupling in this adafruit soil moisture sensor?
Here is the moisture sensor:
https://learn.adafruit.com/adafruit-stemma-soil-sensor-i2c-capacitive-moisture-sensor/downloads
It has a large copper area insulated with soldermask that sticks in the ...
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Suggestion on Power supply design
I am looking for Transformerless power supply design. I have MCU 5V. and would like to drive 12V/24V relay with single LED.
i have 4 pots 10K/200k for timing
So i prefer 230VAC to 12V/24Vdc output ...
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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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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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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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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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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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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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