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# Dielectric Constant fr4

32 Threads found on edaboard.com: Dielectric Constant fr4

## Thickness of FR-4 substrate

Bad idea. 1. u could not get the exact valune of the dielectric constant of fr4 at 33GHz. 2. At 33GHz, loss tangent of fr4 is very large.

## Measuring exact dielectric constant without equipment (after fabrication)

I want to ask how feasible it is in following cases: dielectric constant ~4, frequency 10 to 20GHz Er used in design = 4, in reality 3.8 1) After fabrication of IQ receiver with wrong Er=4. provide test signal to reciever, calculate phase error (IQ must be +/-90 for two test signals). Correct layout according to calculated phase differences

## how to design a FR4 PCB in the layout of a rectifier circuit in ads

for a rectifier board, you do not normally need s parameters unless it is a directional coupler. or microwave you need to choose something like GETEK or a low loss fr4 which has a slightly lower dielectric constant. If you have no board layout software, EAGLE is free.

## FR4 dielectric constant/ permittivity vs. temperature

From 0 to 100 Celsius there are just slightly variation of dielectric constant vs temperature:

## characteristics impedance vs dielectric constant vs frequency

Er is dependent on the dielectric material used (4.3-4.5 average for fr4 based PCBs. Z0 is dependent on the topology used on a PCB design, number of layers proximity to planes etc etc. Download and play with this:

## substrate height of patch antenna

If the height is small relative to wave length, you can calculate an effective height for the layered dielectricum. e.g. H(eff) = H(fr4)/4.4 + H(airgap)

## Microstrip patch antenna

Hello Colleague, - I found an accurate equation for Zc in the book "Antennas for all applications" by John D. Kraus: Zc= Zo/(√ε r[(W⁄t)+2) 92593 Where: Zc= Characteristic Impedance Zo = Intrinsic impedance = 377Ω ε r = dielectric constant from your material: I guess is fr4. W = widt

## Why the measure results are not the same by cable and pcb diff_feed

PCB dielectric Coefficient for fr4 is not constant by frequency so that the manufacturers give this coeffcient for certain frequency,temperature and relative humidity.Therefore the dielectric coeffcient which you used to calculate characteristic impedance for PCB traces migh not be correct. In additional to, if the operating (...)

## Substrate thickness problem in patch antenna

I suggest you use GE fr4 called GETEK which has 10x lower loss tangent than most fr4. W I suspect you are using lossy fr4 and also dielectric constants is much lower at 2Ghz since rated parameter . Also dielectric constant drops 10~20% as f goes up. Return loss of thinner (...)

## Dielectric Constant of FR4 at 13.56 mhz

I am making a pcb antenna which has a resonant frequency at 13.56 mhz and which will be etched onto a fr4 substrate What value for the dielectric constant am I looking for in the substrate at this frequency and why? how can I determine the dielectric constant at a 13.56 mhz given the (...)

## microstrip single patch antenna bandwidth improvement

Hi, I am designing a single rectangular patch antenna . the substrate is fr4 and its dielectric constant is 4.4. I have used Inset feed for the antenna. The frequency is 2.4Ghz. I obtained the following results. My resonant frequency(Rf) is 2.399Ghz return loss @ Rf is 40 db There are many ways to choose the Bandwidth . I (...)

## Specifications of FR4 Epoxy.

Beware that there are many different suppliers, which are interchanged by the PCB manufacturers frequently for cost reduction. Ans all have different dielectric constant and loss tangent. So in short you can only use fr4 in case you can live with these larger variations by taking it into account during the design phase.

## Electrical length while designing a klofenstein taper

Given your physical length of 77.8 mm and effective dielectric constant of 3.27 (did you use fr4 with er = 4.4?), I would expect the electrical length to be in the range: electrical length = 77.8mm*sqrt(3.27) = 141 mm (above the cut-off frequency). This equals a delay of about 338 degrees at 2 GHz. It will be somewhat more because of (...)

## can we determine dielectric constant of material practically

Thanks.... may i get information about practical calibration of dielectric material?

## Stiff PCB material with similar dielectric constant as FR4

Hi all, My 1 mm fr4 board warps all over the place when heated. Do u know of a cheap PCB substrate with similar dielectric constant to fr4 but is stiffer? Thanks You have to compromise either on the price or the quality. Naturally you cant expect sugar at price of salt. :D Cheers

## fr4 dielectric constant

hi all! is fr4 a standard? i mean if one material is said to be fr4, will other fr4 materials have the same characteristics? also, will the dielectric constant change with the width of the fr4? thanks much vpm

## esign a 4 element patch antenna array

hi there, i need to design a 4 element patch antenna array. i have 6inches (w) by 4inches(h) fr4 board. i need to design the array so that feed network, array and impedeance transformer all fit on the stated board can someone please 1)suggest an appropriate operating frequency for the array 2)tell me the dielectric constant, loss tangent (...)

## multilayer PCB with high dielectric constant

Hi, I would like to know if a multilayer PCB with a high dielectric constant (e=10) and low losses at high frequencies is possible to manufacture. Thanks a lot.

## Need to get 4- layer PCB fabricated which has RF chip 2.4GHz

Depending upon your circuit if only transmission lines are there then fr4 is good it has a dielectric constant of 4.4. RT duroid is much much better but costly. You can simulate the results with both materials and can see the difference which is better for you circuit. Hope it helps

## What to consider when designing a PCB for RF circuits?

If you're looking for a check list, here's a basic one: 1) Make sure you know the dielectric constant of the board. If you use fr4, and are really high frequency (say 4 GHz) or higher, you may need to design for losses along traces. This is because the dielectric constant of fr4 is only (...)