Questions tagged [dielectric]
A dielectric is an insulator that can be polarized by applying an electric field. A common example is the use of a dielectric within a capacitor between the metallic plates to increase the surface charge.
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A basic question about using dielectric material in PCB boards in relation to electric field
I was wondering what the PCB's dielectric material(such as FR-4) do to the electric field.
If I'm not wrong, the dielectric material influences how the electric field lines are distributed. And it ...
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Food for thought: Which person has truth in this discussion on capacity and AC? [closed]
I have stumbled upon interesting discussion in the commentary section regarding safety of electrical engineering in home environment.
person1: AC voltage 'flows' even through insulator, fact.
person2:...
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Should reference plane change its potential value if a track goes to another layer?
Assume you have a four layer board.
Signal
GND
Dielectric
VDD
Signal
And you having a track in the 4:th layer. Suddenly you're using a via to go through the 4:th layer to 1:st layer.
Question
The ...
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Determine dielectric constant of unknown FR4 substrate
I have a piece of single sided FR4 PCB substrate that I need to build a 2.4 GHz patch antenna on using copper tape.
Other than the dimensions and it being FR4 I know nothing about the substrate.
Is ...
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PCB material with high dielectric constant
Typical PCBs have a dielectric with a low constant \$\varepsilon_r\$. I'm studying the effect the electrical fields on dielectrics and as an experiment would like to test PCBs with a very high ...
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Hipot arcing for AC and DC hipot test
I have a substrate with multiple conductor traces (0.5mm gap from each other) with aluminum plate on top used as electrode. The aluminum plate is connected to the hipot "line" and the ...
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How to measure the electrical properties to ensure the performance of a thin electrode/insulator stack-up?
I am a mechanical engineer by trade, and I am looking at some basic electrical properties that I need to measure to ensure the device meets the desired performance.
The device consists of a two-layer ...
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Effective dielectric constant in multilayer PCB design
Top => copper
PP1 => RO4350B
L2 => copper
PP2 => FR4
L3 => copper
PP3 => 185HR
L4 => copper
This is my PCB stackup.
In the top layer, I have a 50 Ω controlled RF trace. The ...
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Hipot results vs surface area
I trying to hipot test a 12"x12" metal with kapton layer. Different sizes of metal (e.g. 1"x1", 4"x4", banana plug) is placed on top of kapton tape. The bigger metal ...
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Arc-shape frequency dependence of phase angle in bioimpedance spectroscopy
I have concerned myself with bioimpedance spectroscopy (BIS) from a medical standpoint for some time now, however there is one concept evading my grasp until now:
When measuring complex impedance of ...
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Trying to make a HASEL actuator
I was told that if I apply high voltage to a zip lock bag filled with baby oil with tin foil paper on the end it'd make it contract and act as a HASEL actuator.
I'm afraid of measuring the exact ...
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Voltage required for a spark plug - dielectric constant of air
The dielectric constant of air is approximately 3 kV/mm. The typical space between car spark plugs is between 0.6 and 1.8 mm. By multiplying those numbers in mm by the dielectric constant of air, we ...
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Dielectric strength test voltage
I am preparing an insulation diagram prior to testing a device against IEC 60601-1.
How do I determine the dielectric strength test voltage? I couldn't find anything in -1.
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Why do material makers call the dielectric constant "Dk" rather than "D.c."?
Why do material makers call the dielectric constant "Dk" rather than "D.c."? Is it kind of German? Something like Dielektrische Konstante? It is actually called a ...
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DC hipot leakage current
I noticed that when testing hipot in DC I always get leakage current, but not during AC hipot testing. Do you have any ideas about this? My hipot tester is Quadtech Sentry 500VA. I’m testing a ...
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