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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Use of Split Planes
sorry for multiposting but I have a lot of doubts on PCB Design. On my design, Texas Instruments (the chip manufacturer) tells that:
"Never route signals over splits in their perspective ...
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How Prepreg types and number of plies affect mechanical and thermal properties of the PCB
What are advantages and disadvantages when using a single ply of 7628 type prepreg as compared to say 2 plies of 1080 or a similar prepreg. I'm primarily concerned about any mechanical and/or thermal ...
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Prepreg thickness: ECAD specs vs. fabrication result
I have a question concerning the thickness of the prepreg layers in a PCB. If I understand correctly, the prepreg layers are used for "gluing" together the core(s) and copper foil layers.
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LED Array Controller Circuit PCB Design Questions and Feedback
Background
I'm designing a LED controller based on a Teensy 4.1, some AD9833 Function Generators and some TLC5948 LED Drivers. I'm aiming to make an instrument of sorts, specifically a POV display ...
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Why has the auto-router put my PCB traces on two different layers?
This is my first PCB design.
I want to design the PCB layout of the following switched mode regulator:
This is the resulting PCB layout in which I've placed my components and the auto-router function ...
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Altium Shortcut to cycle through all PCB layers one by one
I wonder if there is any shortcut in Altium to cycle through all layers of a multilayered PCB one-by-one? That is to say that when the shortcut is first entered 'Single layer mode' is selected and ...
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PCB 6-layer stackup problem
I'm currently designing a PCB with double side components and I'm limited to 6 layers max. The project has couple of MCUs at 84 MHz. There are USART, I2C, SPI, some analogue lines and high-power lines ...
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How to show component value on Altium Silkscreen?
The Silkscreen of my Altium PCB project only shows Reference Designators of components. I want to show component value or part number instead of the reference designator on the silkscreen. Is there a ...
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PCB Layer Number Standards?
Is there any standard or common numbering system for PCB layer numbers? I'm using Altium.
I imported a few different components from a couple of libraries and found that they put things like ...
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Choosing the correct Ground or Power net for internal copper planes in a 4-layered design
I am a chemistry student trying to replicate a PCB circuit as part of an extra-curricular challenge. I am in over my head, but I am learning a lot and don't want to give up. I tried to route the ...
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surface/external edge coupled microstrip vs (internal) asymmetric edge coupled microstrip
In the process of determining the track width/separation of differential pairs for a board design
that needs to route usb2, pcie(90R) , gigabit ethernet(100R), CSI/DSI(100R), HDMI
im looking a a four ...
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KiCAD: Weird ratsnest
I am in the process of hooking up the ratsnest in pcbNew, in KiCAD.
I finished with the process, except the last connection.
Here it is:
The upper copper layer is set to Vdd. As you can see, the ...
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4 Layer PCB Local Pours on Signal Layers
I'm in the middle of placing components on my first 4-Layer PCB. Layers are Sig-GND-Vcc-Sig. I2C/SPI/UART, up to 20MHz MCU, nothing exceptionally fancy.
I have decided to check with the community ...
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4 Layer PCB Standard Stackup Grounding
I'm about to start placing components on my very first 4-Layer PCB (wrapping up schematic and MCU software tested on 2-layer pre-prototype, all runs surprisingly ok, but still 2 layer meh). I've ...
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I mixed VDD and VSS plane in a 4 layer PCB - Does it matter?
I made a 4 layer PCB according to a recommendation from this datasheet
https://www.ti.com/lit/ds/symlink/dp83848-ep.pdf?ts=1613467684339
Signal
Ground
3.3v
Singal
But instead, when I notice how the ...
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4 layer stackup, inner layers GND & PWR
To "somewhat" quote Rick Hartley, "the energy isn't in the traces & planes but in between", I'm now wondering, when I use the following stackup:
Sig
GND
PWR
Sig
You would ...
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Routing Differential Lines vs PCB Fabrication Constraints
I'm in front of a big question. I need to route 90 Ohms differential lines for a USB 2.0 Project.
I understand how to use tools like Saturn PCB Design to give me the correct spacing and lines width.
...
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Supplying power to op-amp using Via
In my PCB, I am bringing voltage source through the bottom-layer and connected to the supply pin of op-amp on top-layer using via (Drill diameter - 0.3mm) as shown in the figure below.
I have doubt ...
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Connecting PCB power planes and polygons
i am making a 4 layer PCB board and in that the inner two layers are ground planes between top and bottom signal layers. I want to know do i have to connect the top layer(signal layer) with ground ...
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How do you decide on having more than two layers to have on a PCB?
I just started writing my bachelors thesis. I have been working as a junior hardware designer for a little less than a year now. All the boards I have designed until now have 2 layers. For my thesis I ...
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4-Layer Stackup PCB design
I was designing a 2-Layer PCB and now I'm stuck. I have routed like 80% of all nets and now I'm no more sure if it makes sense to continue. It's getting pretty messed up with all the crossing routes ...
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PCB manufacturing - Why etch resist such as Tin is removed after the etchant has removed the unwanted copper
Alright so I'm learning the PCB manufacturing process.
I have seen many professional PCB manufactures use "Tin" to be used as an "etch resist" which protects the copper traces ...
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Is it bad practice to place a bypass capacitor under its respective component?
I am designing a double layer board and in my layout I am running into problems.
I want to keep the board as small as possible, but I should also be able to assemble it per hand. I made all my ...
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Electroplate a circuit onto fr4?
I've been looking into making my own pcbs and was thinking I may try printing the circuit on to the fr4 with carbon and electroplate the circuit on. After a while on google I havent found any info on ...
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Crosstalk in PCB layout
I am designing a 4 layers PCB with the following stack-up:
Signal flooded with GND
Solid GND plane
POWER plane
Signal flooded with GND
For the top Layer I want to divide the GND plane (flooded) into ...
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tear drops disappearing during mirroring in altium
I have recently faced a problem...whenever I mirror my pcb by using the shortcut>>M+i
all of the tear drops which are defined in my design will be disappeared! does anyone know why this problem ...
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How should DDR ram layouts at PCB? [closed]
I am designing a board which include DDR3 Ram, AM335x Series MPU. I have a question at this topic.
How should it DDR Ram layouts at PCB? Can I draw at top layer? Or which layer the best? I want to ...
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What is the USB like connector on this PCB?
I am just jumping into the world of electrical engineering (coming from software development) and I am examining some PCB’s trying to find UART, JTAG connections, etc. I’ve come across a board with a ...
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Multi-layer Via-in-pad with 0.5mm Pitch BGA in KiCad
I am working on a 4 layer board with an 81 pin 0.5mm pitch BGA which effectively requires via-in-pad for dropping down to other layers. Decoupling must be done on the bottom as there is no space for ...
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how to design step groove pcb in altium designer
I need to design a multilayer pcb in altium designer that has cutout just in one layer. I was seeking that and I found out that in china it is called 阶梯槽. I translated to English but I didn't find any ...
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Calculating maximum permissible track amperage for intrinsic safe PCB
I'm reading IEC 60079-11 standard (Equipment protection by intrinsic safety "i") which discusses how to design intrinsic safe circuit boards. In section 5.6.4 it talks about permissible ...
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What happens if the Ground plane is expanded/poured in the VCC/Power layer in the multilayered PCB design? Is that recommended?
I just wanted to know what are the advantage and disadvantage expanding the ground plane in the VCC/power plane in the multi layered PCB.
Below is the 10 layered PCB stackup:-
TOP,
Gnd,
Sig 1,
Sig 2,
...
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Rigid-Flex PCB Fabrication: Window opening vs slot opening
We had issue with one of the rigid-flex design cracking at the joint of Rigid and flex intersection.
It is important to note that this is second batch of same PCB and PCB was not cracking in first ...
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4 layer buck converter layout
What is the standard layout for a 4 layer PCB that everyone follows for a buck converter or similar? I was planning to go like this:
Signal
Vcc
GND
Signal
Since inductors and FETS are noisiest of ...
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Use the metal in a metal core PCB as the GND layer
As I understand in a metal core PCB there's a copper layer, thermally conductive dielectric layer and then the metal layer for the heat dissipation. Can vias come to this metal layer so that it can ...
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What does "TYP" mean in a datasheet?
I am designing a PCB model of the ATmega32 using Altium Designer
I have found the word "TYP" in the dimensions of the ATmega32 in the datasheet.
What does this word refer to?
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Gerbers to PCB conversion - Altium
I am new to Altium. I am trying convert gerber files in to PCB. I am getting following error while trying to extract net-list.
It is asking me to compress or redefine layers. I dont know how to do ...
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About the mechanical layer in altium PCB
I have downloaded the footprint for ATmega32 SMD as in the figure my question what is the need for the mechanical layer with purple and green colors in this foot print (and after fabricating the ...
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W5500 2-layer PCB or 4 layers?
I am in process of hiring a freelancer to develop a PCB which will incorporate Wiznet W5500 ethernet IC.
Some have suggested a 4 layer PCB, but some are saying it is possible in 2 layers.
As the board ...
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How to decide whether to place a microcontroller on the top or bottom side in PCB layout?
How to decide whether to place a microcontroller on the top or bottom side in PCB layout?
What are the advantages on the top side?
What are the advantages on the bottom side?
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Is it OK to route power traces underneath an MCU?
I am working on a 2 layer PCB: a STM32F405 break out board with I2C, SPI and UART. I am trying to minimize traces on the bottom ground plane and have arrived at a layout in which I have routed power ...
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Starved thermal on GND or starved thermal on power
These errors can make me a short circuit in my PCB which consists of 4 layers (top, power, GND, bottom.)
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Least resistance in PCB trace
If you have long PCB traces and want to minimize the resistance, is it feasible/viable to use through hole vias to be able to utilize copper on both sides of the board? If width of the trace is ...
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Routing decoupling capacitors to a micro-controller
I'm attempting to design and make a Keyboard PCB and have stumbled onto a question I can't seem to find online (probably because I'm not searching for the right thing/lack of info)
When routing ...
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Advice for pcb that didn't print correctly
I designed a schematic with quite a lot of connections (88 comparators into 14 MUXes) I created ground planes on the top and bottom layers to assist with the many ground connections. I just got the ...
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What is the polygon pour and power plane for in a PCB?
I am newly in PCB design. Can any one explain me what polygon pours and power planes are used for in Altium PCB, or give me a link that explains it?
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About the difference between ambient temperature and rise temperature in pcb design
When to use to
Pcb trace width calculator,there are two factors,ambient temp.and rise temp...what is the difference between them?
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Sizing of different PCB polygons on different layers for high current
I need to design some traces or polygons for high current (15A) on a 4 layer Lithium Battery Management System board, but I am unsure about their sizing.
I am following a reference design from TI, ...
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Ground vias use on no-trace areas at a 4-layer PCB
Background info:
I am using a 4 layer PCB stack: Signal, Gnd, Signal+Power, Signal (mostly ground). To avoid out of question issues, I use this set-up due to a reference design on Texas Instruments as ...
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PCB Layers power and ground plane
I have noticed that professionally done board always fill top and bottom with GROUND planes. As i have been making PCB board myself i find that having the top layer POWER fill and bottom layer a ...
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