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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Does supercapacitor electrode need dielectric layer?
I am trying to build a super capacitor. I use Activated Carbon with Wood Glue, aluminium tin can as electrode, multi layers of tissue paper as separator, and table salt water as electrolyte.
No matter ...
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Characteristic Impedance of Multi-Dielectric Coplanar Waveguide
Background
I've calculated the characteristic impedance of a CoPlanar Wave Guide (CPWG) type transmission line on my 8-layer stack-up between L1 - top layer and L2 - GND1 directly underneath it. The ...
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Refractive index, wavenumber, and wave impedance of the PEC that a plane wave is normally incident on
I am trying to find the refractive index \$n_t\$, wavenumber \$k_t\$, and wave impedance \$\eta_t\$ of a perfect electric conducting medium t. Here is my work so far:
The conductivity of the PEC is \$...
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Impedance of an embedded microstrip with different sub- and superstrate
I have been trying to find a formula to calculate the impedance of an embedded microstrip where the substrate has a different dielectric constant to the superstrate (so the stack up is conducting ...
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How to design an amplifier for a sensing liquid level using capacitive probes?
In this problem I have a capacitor that is submerged in a varying level of dielectric fluid. Therefore, the capacitance varies linearly with the height of the fluid. How should I design a simple op ...
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How fast is DC current/voltage?
The standard way to calculate the speed of information (current/voltage, EM wave) through a dielectric medium (like PTFE or fiber) is to determine the relative dielectric constant, and compute the ...
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Calculating the permitivity of PCBs
I've read that the permitivity of FR-4 is around 4.5, however I would like to measure the permitivity of an actual double sided copper clad board, the way I am thinking is to measure the thickness of ...
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Can you use 'Rubber,' Specifically Liquid Electrical Tape Between The Plates of a DIY Capacitor
The above is pretty much all there is to the question. By "can you," I mean will it be properly effective / are there any tips? If not, why? It seems that this ought to work, but I can't ...
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Can I calculate minimum rise time of a transmission line if I know the length and the loss tangent?
Overview: I am trying to work out if it's possible to transmit my 1.2Gbps MIPI data down a 600mm long flexible PCB strip. Assuming I have the impedance correct, will the signal still be degraded by ...
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BIL, Dielectric Breakdown, Shrink Wrap, and Safety. Is there a resource for this information?
I am currently working with a system that produces high voltage transients for system testing, and have some cables that need to be made/modified to work with some new equipment.
The operating ...
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What material should I use for the plates of my homemade mica capacitors?
I recently acquired some mica as i want to build my own high voltage (50 kV if possible) capacitors. The problem I am encountering right now is that the surface of such a crystal isn't perfectly flat ...
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What material can I use as a dielectric in my own high voltage capacitors?
I need capacitors rated for 50 kV. Buying them is an option but the ones with appropriate voltage rating I have seen cost more than 50€ which is far too much.
That's why I want to make caps on my own ...
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Relation ship between Track width, Impedance, Dielectric and copper thickness
I like to know the relationship between different factors like track width, impedance, dielectric and copper thickness.
After quite a reading I got to know that as the track width of a cline is ...
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How come distilled water hasn't replaced transformer oil as a high voltage insulator?
I've noticed that distilled water has an extremely high dielectric straight (65-70 MV/m).
With that considered, how come it isn't used in the place of transformer oil for 10-20 kV applications where ...
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PCB Layer Stack Dielectric Constant Math
I have a question reference PCB layer stack and the adding multiple dielectric constants together.
The image and description below should help clarify the question:
The differential pair will be ...
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