Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [pcb-layers]

Printed Circuit Boards (PCBs) are composed of a sandwich of alternating layers of insulating substrate and conducting copper layers. The copper layers are etched to form connecting tracks between components as well as earth/ground or power planes. The simplest PCB has one substrate layer and one copper layer. Generally only the copper layers are counted. A complex PCB might have seven layers.

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The best stack-up possible with a four-layer PCB?

I'm designing a 4 layer PCB and I know that the standard stack-up is Signals GND VCC Signals (GND and VCC can be switched depending on the layer with more signals) The problem is, I don't really want to connect all ground pins through vias, there…
mux
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What exactly is prepreg and core in a PCB?

I am trying to wrap my head around the structure of a multilayer PCB, and while I can understand many things, I am not able to grasp the concept of "prepreg" and "core". What do they exactly do? I have attached a reference stackup below. Only thing…
LoveEnigma
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Breakaway PCB Design

I am aiming for a breakaway PCB design for a small series where an unneeded compartment can be broken off. (See Image below) I saw this for example on the STM32 Nucleo boards, where it is used to take off the flash interface once you're done with…
mxcd
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PCB Ground and Power Planes

I am desigining a 4-layer PCB with the following stack-up: Signal Top, Ground Plane, Power Plane, Signal Bottom. This is the first PCB I make like this, which includes a noisy SMPS with a switching frequency of 600KHz, as well as a 32MHz uC and a…
Reuven
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Is it proper to use an internal layer as a heat bed if I want to warm my multilayer PCB?

I need to design a circuit to warm my PCB. There are many ways to build up such circuit. But I learned from a post "Warming PCB in a low temperature environment" that maybe I can use traces as heater. My first idea is to use one of the internal…
billyzhao
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How do I disable clearance check for a layer or for only some certain elements?

I'm designing a PCB in Altium Designer. There is a very large heat sink in my project. When I put it on the PCB, there will be plenty of empty space under it where I can put other small components. I tried to put some part of this bridge rectifier…
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Mixed Signal PCB, 2 or 4 Layer?

I'm currently designing a mixed-signal PCB for a client and I've been reading a lot about signal integrity and most of the books recommend a 4 layer board (or more) because of the noise resistance from having a solid ground plane and reduced…
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Return path on a PCB

I've spent the weekend absorbing video lectures from Eric Bogatin and reading his book "Signal and Power Integrity - Simplified" He states that the the return path for the PCB may be any DC plane which could be a VCC rail underneath the signal…
efox29
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PCB's and designing power connections

I've designed a few PCB's now, but never put much thought into good practices. They were small boards and most of the emphasis was put into just making sure everything that needed to be connected was connected. Now I want to get more serious into…
bwoogie
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PCB, pads with holes but with different nets on top and bottom sides

I need pads with holes in by PCB, but the top and bottom side of the pads need to have different nets i.e. the top and bottom sides must be isolated. Here is the picture Is this possible to fabricate for the PCB manufacturers? If yes, how do I…
zud
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Which is better for signal integrity in a two layer PCB? Two ground planes or one power and one ground plane?

I am designing a two layer PCB with high speed signals with rise and fall times as low as 3ns. I was doing some studying and learned that for better signal intergrity and EMI a good grounding strategy is critial. To lower the effects of displacment…
Bubu
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Purpose of multiple layer PCB without possibility of blind/buried vias?

What's the purpose of multiple layer PCBs (i.e. 4 layer,) when many manufactures like JLCPCB can't produce blind/buried vias as they just support through-vias? Let's say I have an SMD component with a GND pad on the top layer (1st layer) and the GND…
Dakalaom
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Is it always possible to reduce the number of layers on a PCB by making the board larger

I see that a 2 layer PCB is really cheap to prototype. A 4 layer PCB is almost 4x more expensive . I have a design that uses DDR3 RAM where I need to match trace lengths. However I also need to keep the costs down. I observe that going in for a…
Rock Tumbler
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4 layers PCB stack - (signal, signal, power, ground)

I've developed a board for a project and the company that is going to assemble it in a pluggable module has just asked me a weird modification. Currently it's a 4 layer board: top signal, ground, power, bottom signal. Pretty standard. They want me…
FlyerDragon
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What is the "Eco1.User" layer in KiCad?

In KiCad (Pcbnew), and perhaps other PCB layout programs, there is an Eco1.User layer and also an Eco2.User layer. What does the "Eco" stand for? And what are these drawing layers typically used for, in particular, do they have an "official"…
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