Questions tagged [capacitive]
Based on the usage of capacitors, condensators. Alternatively, utilizing the derivative of signals.
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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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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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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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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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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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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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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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Connecting GND to PE to improve touch sensors sensitivity
I am designing a smart light switch based on a microcontroller, with touch buttons. The design consists of two PCBs: a low voltage one for power (230 V) and an extra low voltage one for control (3.3 V ...
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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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Measure capacitance on a mutual capacitive touch sensor
I interpret the mechanism of a mutual capacitive touch sensor like this:
There are 2 electrodes X and Y. To measure the difference in capacity, the X electrode is driven high (i.e 3.3 V) and the Y ...
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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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Matrix Trackpad
I wanted to build a matrix capacitive trackpad. Ideally, its PCB would have 4 layers:
1--> The plate array
2--> The circuit that links the rows (horizontally)
3--> The circuit that links the ...
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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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