Questions tagged [ground-plane]
An area of copper on a PCB which is connected to the PCB's ground node in order to provide a return path for current from the various circuits on the board. The ground plane's area is typically made as large as possible (even occupying an entire board layer) in order to minimize its impedance, thus allowing it to conduct high return currents without a significant voltage drop from one part of the board to another. Use with related tags such as "pcb".
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Should I really divide the ground plane into analog and digital parts?
I am about to design my first PCB as part of my graduation project.
Of course, as the first step, I try to learn as much as possible. A part of the research I found this 3 part article, that suggests ...
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Why does 1/4 wavelength have a ground plane and 1/2 wavelength needs none?
Why does 1/4 wavelength have to have a ground plane and 1/2 doesn't?
I know that an antenna that has half a wavelength does not need the ground plane (example a dipole antenna) and when using a ...
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Reasons not to fill unused board area with power planes instead of ground planes?
On the (two-layer) board I'm designing, I have a relatively large unused area. Instead of just pouring it with ground on both sides, I'm considering filling it with Vcc on one side and ground on the ...
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Why exactly is it discouraged to gap the ground plane?
From time to time I hear (and read) that it is not good to make separate Gnd planes for digital and analog circuit parts. It's all summarized in this rule of thumb: "Don't split the Gnd plane, don't ...
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How to minimize impedance from capacitor to Gnd and Power planes
I'm trying to minimize the impedance from my capacitors to the Gnd and Power planes.
1. Via positioning
I've learned from several sources that the best via positioning is close to each other. This ...
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Should there really be 1 MΩ resistance between an anti-static wrist strap and a pc?
My previous question: what exactly is grounded through motherboard standoffs?
The answers suggest that a PC case is grounded in 2 ways:
To the ground plane of the motherboard, through the brass ...
user127725
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Purpose of exposed ground pads
I have a Beckhoff EL2008 8-channel digital output terminal that I took apart because I'm using an ASIC that is inside the module, Beckhoff's ET1200.
There is essentially a ring of ground pads,some ...
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Should I fill free PCB space with ground?
I'm new to PCB design and I'm wondering if it makes sense in a two layer PCB to fill any free space on the top and bottom layer with a ground area.
My design:
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Should there be any PCB ground plane under a 16 MHz oscillator?
For a 2-layer PCB,
should there be a ground plane under a 16 MHz oscillator?
From this PDF document,
http://www.nxp.com/assets/documents/data/en/application-notes/AN2500.pdf,
it shows the following ...
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PCB antenna: ground plane layers and dimensions?
I'm using an Inverted-F antenna on a Bluetooth Low Energy peripheral/device I'm designing and I'm not sure how I should design the ground plane.
The ground plane should not be "too big" nor "too ...
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Confining signal using stitching vias on a 2 layer PCB
I have read in some questions (for example: Via Stitching on 2 Layer PCB when top layer is not fully ground pour ), that stitching vias are useless when one's PCB only has 2 layers, however people do ...
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What are the different grounds on a PCB?
I am working with boost converters recently. I have problem which you can find here.
After going through the datasheet several times I encountered the special focus on the ground plane. It talks about ...
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15MHz photodiode PCB, feedback requested
I've developed a 2-layer 15MHz photodiode amplifier board. The first stage is a transimpedance amplifier using AD8065. The second stage is using a current-feedback amplifier, THS3091. Power is +/-12V ...
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The curse of the ground loop
Sometimes it feels like a ground-loop is inevitable. Please follow along the following thought-experiment. It would be wonderful if you could provide solutions to the issue described.
Imagine a board ...
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What's the best ground topology for this mixed signal board?
I'm designing a 4 layer mixed signal PCB with sensitive analog circuits and RF-digital circuits. The board have many mechanical constraints so the places of the analog and digital circuits are fixed.
...
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For a 4 layers PCB (with ground plane), covering with ground polygon on Layer 1&4 necessary?
For a single or double layered PCB board, usually I will cover all the empty spaces in the layout with Ground.
This is the 1st time I am designing a 4 layer PCB layout.
Layer 1: top signal (high ...
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Placement of RF module for better performance
I am using a standard RF module (i.e., Bluetooth-module-on-PCB), which has a PCB-trace-type anntena. It is in turn to be soldered onto my main PCB. The whole thing will be powered by a standard Li-ion ...
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How on earth shall I design the ground planes for mixed signal circuits, split or not?
Our circuit is like following:
There are four layers, including top, power, ground and bottom.
My way of grounding:
I follow the instruction by Maxim: https://www.maximintegrated.com/en/app-notes/...
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PCB layout - ground plane clearance around and under a ceramic resonator
We are using Murata's 4MHz ceramic resonator (CSTCR4M00G53-R0) in one of our designs and request help in PCB layout design around the ceramic resonator. The below Murata's FAQs page suggests not to ...
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Its ok use different layers for power?
For example in a double side board I'm using one layer as gnd and the other layer as power, and then I route the whole circuit inside the planes.
Is that ok? Because I saw that usually both sides are ...
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Stripline reference plane discontinuity in reference design
According i.MX6 SMART DEVICE SYSTEM of freescale layout board, it uses 8 layers, my question is about the inner layers, they are striplines with a continuos GND plane in one side but in the other side ...
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Additional signal plane vs lots of vias
I have a circuit that I am currently designing using a 4 layer PCB (signal, ground, power, signal). The PCB has rather a lot of vias to route the signals around the board (there are size constraints, ...
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What's the purpose of the ground plane?
What's the purpose of the ground plane?
I guess it's a pretty basic question and I tried to understand it by reading http://en.wikipedia.org/wiki/Ground_plane#Printed_circuit_boards but I still don't ...
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Should vias be used for every GND connection?
When making a two layer board with the bottom layer being a GND plane, should every GND pad for ICs and passives be directly connected to the GND plane using a via, or should I route all of the GND ...
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Split or not split the ground plane in a low-noise design?
For low-noise design, many component datasheets suggest dividing the ground plane into AGND and DGND and linking them with a star connection.
But my ten years of experience in EMC have shown me that ...
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What is the best way to route a two-layer MCU based PCB?
Considering we're designing a two-layer PCB with a 100-pin MCU, what's the best way to routing? As you can see in the image, many pins of this MCU are used (almost all.)
When designing a two-layer ...
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How does Stitching capacitor provide shortest return current path between plane splits, as we know that it blocks DC current?
I heard that Stitching capacitors are used to provide shortest return path whenever a signal is routed along the 2 power plane splits. As we know the return current path will be right under the trace. ...
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'Unrouting' a ground plane on Eagle
I have been using Eagle for quite a while now but there is one thing that continues to bother me while I am using it. I have made the ground plane cover the shape of the board, however, when I am ...
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Why are copper pours called copper pours?
I was adding a ground plane to a PCB layout today, and my curiosity peaked. Virtually every EDA package uses the term "Copper Pour." Why is it called a copper pour? It doesn't really make sense ...
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Can a ground plane be used as a current return path? (DC only, no signals, no AC)
I'm creating an adapter which hosts two connector types and simply routes two connections from one connector into the other.
Only two traces/connections are used; Vcc (about 6v) and GND
Operating ...
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PCB layout review: ground layout for CC step down converter
I'm laying out a step down converter based on the ST L5973AD being used in constant-current layout to drive LEDs, per Application note 2823.
My previous question was what is the datasheet telling us ...
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PCB Layout Help (with schematics!) - Split ground plane or not?
Obligatory "not an EE, just a ChemE trying to make some pressure readings for science"!
Schematic attached, along with my current layout. It's a 6-channel pressure sensor using MPX4115AP sensors and ...
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Power origin and power planes placement on PCB
Although there are many similar questions to this one, I wish to get your attention to this specific board layout.
The main power on the board will be 5V, and one of the layers is dedicated for this. ...
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Benefits of top and bottom ground pour in multilayer boards with proper ground plane layers and stackup
I'm trying to get some analytical feeling for the use of ground pours on bottom and top layer in multilayer boards with proper stackups such as (for example).
Top
Gnd
Sig1
Power
Power
Sig2
Gnd
...
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Effects of ground plane size on antenna gain
I have looked online a bit and it seems to me that the general belief is that the larger the ground plane (up to a certain extent), the better.
I am trying to design a patch antenna, so I ran several ...
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Avoiding noise coupling by power switching to ground plane in multilayer PCB
I've a 4 layer PCB in which I've to layout a power switching supply mixed with digital signal circuit.
My stack up is:
Top Layer: component and routing (power net and signals)
Internal plane 1: GND
...
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Why are there so many signal grounds for PCI Express?
PCIe connections have one to two ground contacts per differential signal pair. Why is this the case?
On the boards that I have been studying, all of these pins are tied together onto the same ground ...
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KiCad ground plane error or DRC glitch?
I have a PCB that when I run a design rule check in KiCad I am getting an error that an IC's earth pins are unconnected to a via which is also connected to earth. I don't get these errors a lot so I ...
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Does putting solder mask over a ground plane influences its heat exchange with the air?
If you want the best thermal exchange with the air, is it preferable to leave a thermal/ground plane raw or to cover it with solder mask? And how important is the difference?
(Dave from EEVblog is ...
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How to make a ground plane for relay PCB switching mains?
I am making a PCB board with 4 relays controlled by a PIC microcontroller as shown. The board consists of components that are working on 5V DC and the relays that are connected to 110VAC. I had a few ...
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Bonding yourself via GND pin of an USB-port?
A simple EPA (ESD Protected Area) consists of 3 things:
wrist strap
antistatic mat
common point ground
When doing field service (installing/replacing hardware parts) the ESD sensitive part goes ...
user127725
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Altium split power plane
The layer stack manager has created a power plane for me on which there is a default polygon pour that is the board size :
For some reason I can't do a polygon pour on that layer... I would like to ...
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AC signal and ground plane with another trace passing between - is this bad?
In learning about reducing a circuit's EMI emissions, I've learned the importance of a ground plane, in that it allows the current-return for an AC signal in an adjacent layer to flow directly under ...
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Multiple ground planes with optocoupler
I'm designing a circuit that uses an optocoupler to isolate a relatively noisy H bridge from the USB circuitry also present on the board. Clearly in this case I will have two grounds - what is the ...
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Is it OK to place ground plane under transformer?
I have a large transformer (50kHz, ferrite E-core) on the PCB. I want to pass power rails under it on the bottom layer. Should I place a large ground plane on the top layer to shield these power rails ...
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PCB design review: Questions about power/ground plane
I am designing a small four layer PCB with KiCad. The purpose of this PCB is to control and monitor the lights of a car (not for road use) and without having to resort to old relays and fuses.
I have ...
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Gerber lines in ground plane
My manufacturer is asking me to remove those lines from the ground gerber layer
The design was made in eagle, I've been searching information about this problem and I've found nothing, I don't know ...
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Power and Ground planes The Henry Ott way or split ground planes
Seeing a lot of mixed infomation around involving ground planes on multilayer boards. For a mixed signal mulitlayer PCB which is the preferred method? I know every board is different and it depends ...
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Shield in Inner Copper Layer
I have been designing second version of 4 Layer PCB. The PCB has connectors all over the PCB. In the first version, I had Copper Pour (I call it ...
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Connecting Analog and Digital Grounds
I am designing a system that incorporates an FPGA, a few ADCs, and a few DACs. I am curious as to what my best options may be for grounding in my system.
The FPGA is on its own daughter board, but ...
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