Questions tagged [capacitive]
Based on the usage of capacitors, condensators. Alternatively, utilizing the derivative of signals.
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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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Capacitance of semi-cylindrical plates?
For a visual reference of what I mean by semi-cylindrical plates check the diagram below.
EDIT:
The above diagram is not what I intend to implement. It is just to show anyone trying to answer the ...
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What material can I use to block a capacitive touch from registering?
I am a self proclaimed tinkering problem solver, but this one has me absolutely stumped!
I have a capacitive touch switch panel with six touch areas that close or open a relay to supply power to ...
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Calculate -3 dB point in low pass inverting transistor audio amplifier
What I am trying to do:
I am looking to find the \$-3\ dB\$ frequency for my common emitter transistor amplifier with a capacitor in the feedback loop.
I have somewhat of an idea, but I wanted someone ...
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Looking for a large capacitive touch array controller
I'm building a capacitive touch panel.
It has an odd shape, so I resulted to building my own with the capacitive diamond array solution.
It doesn't have a screen underneath, so it's all contained on a ...
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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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resistor placement in inverting amplifier to minimise noise coupling
(Image is my own creation.)
I notice that an inverting amplifier can be very sensitive to capacitive and inductive noise coupling on a PCB. I was wondering whether the placement of the R1 resistor ...
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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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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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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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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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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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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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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 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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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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Vintage capacitive switch
I have this switch from a Philips Electronic 212 turntable. It’s simply two metal pieces, one a ring and the other a button-like center. I’m not sure, but I think it is a capacitive sensor or button.
...
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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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Purpose of electronic elements in a capacitive dropper circuit
I have found a capacitive dropper circuit in an LED light bulb:
I have a few questions about this circuit:
Normally, in capacitive dropper circuits, I would expect a resistor parallel to C1. I am ...
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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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Sine wave CMOS buffer from inverters with or without feedback
Is it possible to buffer a sine wave using inverters alone or with some kind of feedback?
I've been browsing google for minimalistic (I'm in 3.3-12 V domain) sine wave buffers and this thought stuck ...
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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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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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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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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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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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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 ...
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Capacitive touch sense problem with battery powered laptop
I designed a PCB that includes capacitive touch. The circuit works with 5V powered from USB.
When Laptop is connected to 220V line, the PIC can sense capacitance variation.
When Laptop is not ...
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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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Time delay circuit to reverse the rotation of DC motor when input is high
I am trying to design a circuit to use to control a DC motor according to the output of a capacitive proximity detector.
The circuit should turn ON the DC motor in forward direction when the hand ...
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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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Convert capacitive touch sensing back to mechanical switches?
Capacitive sensing seems to replace often mechanical switches. Is there a way to convert them back to mechanical switches?
Problem at hand is a cooking device with interfaces with the user via the ...
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Pre-charge resistor and contactor power dissipation calculation
I am building my e-motorcycle. I am planning to use only one contactor instead of using three contactors. In my plan, pre-charge resistor and contactor circuit will be main contactor too. I am curious ...
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Bypass touch sensor IC with a button?
I want to replace a capacitive touch sensor on a circuit board (I think it’s a TTP223) with a tactile switch to overcome over/under sensitivity issues. I have wired a switch to ground and the CMOS ...
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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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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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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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How do I achieve well-formed pulses in a Dickson charge pump?
A picture is worth a thousand words, and I tend to make a lot of mistakes in my words, so, first picture, the circuit in question:
I know the Dickson charge pump looks a little different but it is ...
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What is the maximum reasonable cable length for a humidity sensor?
I have an ESP32, and use capacitive soil humidity sensors to check the humidity of my plants. They get shipped with about 15 cm of cable attached.
What is a reasonable/safe cable length I can use ...
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How to design an accurate high tripping voltage capacitor discharge circuit
We have a system which discharges a capacitor (20 uF) charged to approx. 3kV DC using a spark gap. The principle is simple, when the voltage exceeds a certain value, it jumps the gap (around 0.6 mm) ...
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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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I want to know if the following circuit is inductive or capacitive. What is the difference between inductive and capacitive?
I want to know if the following circuit is inductive or capacitive? What is the difference between inductive and capacitive?
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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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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 to make fast (low latency) capacitive touch buttons
I'm looking to create low latency capacitive touch buttons for a musical instrument. The response time (from physical touch to touch registered in microcontroller) needs to be around ~2ms or less.
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Does max OP Amp Capacitive Drive Capability Matter with Active Filter?
I know that every OP Amp does have a limited capacitive load drive capability.
Even if not specified, it is always a good practice to use a series isolation resistor.
Anyway; when looking at an active ...
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How to drive 400 nF load with DAC
I need to drive a some kind of pzt transducer with a triangular 6 Vpp voltage. The transducer is modeled as a 400 nF capacitor. I want to drive it with 10 kHz 3-9 V triangular voltage however my DAC ...
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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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How to create a clearance area around a single PAD in Altium
I'm creating large circular pads (13.5 mm diameter) for some capacitive buttons on ALTIUM.
I want to create a circular clearance non-copper space area around each of these pads (around 1..2 mm) to ...
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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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