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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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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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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How do I design correctly ground plane separation for Texas Instruments TPS63060 IC?
I'm concluding my two-layer PCB design and my last obstacle is ground planes.
Specifically, the problem is the TPS63060 IC that requires Power Ground separation from Control Ground (pin 7). That is a ...
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4 layer board back bypass capacitor power plane connection guideline reason
I'm reading Power Bus Decoupling Guidelines for Printed Circuit Boards with Widely Spaced Power Distribution Planes.
And they have these recommended connection configurations for bypass capacitors ...
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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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Multiple ground
In my design I have four different ground:
Ground: from USB for step up and battery charger IC.
Ground1: for a split supply (virtual ground).
Ground2: for the input signal reference.
Ground3: for 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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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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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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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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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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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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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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How do I know where to put stitching vias?
I'm working on a PCB that allows me to attach a TSSOP IO expander to a breadboard more easily for experimenting. I asked a question regarding the configuration of decoupling capacitors for an IC with ...
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Extent of ground plane beneath filtered DC converter?
I'm laying out the PCB for a small and simple power supply to feed some audio amplifiers. It will feature a DC -DC converter module and I'd like to filter the output for 1) extra smoothness 2) learn ...
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Question about analog and digital ground planes
I am using a microcontroller with an integrated DAC. On my 4 layer PCB, I have connected the digital and the analog ground planes below the microcontroller.
The microcontroller and the DAC are ...
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Traces over ground plane [duplicate]
Sometimes it cannot be avoided to run traces over a ground plane (bottom layer) in a two layer PCB.
I have two questions regarding this:
In the (simplified) example below, what is preferred? To use ...
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Connect signal ground to safety ground?
We are designing a product which has to meet EMC directives. It consists of metal backplate folded into a chasis (the front is open). on the backcover there is a SMPS mounted. and on top of this we ...
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Why are laptops grounded to earth via 1 MΩ resistance but desktops are not?
I measured a few laptop AC-to-DC adapters. They have 1 MΩ between the GND pin (goes into the laptop) and the earth prong (into the wall).
Desktops are grounded directly to earth: 0 Ω.
Why this ...
user127725
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Ground plane under power inductor in DC to DC converters
Is it a good idea to put ground plane (fill the area with copper) under the power inductor in DC to DC converters?
I was looking for answers about step down regulators but I would like to know about ...
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Does a Vcc layer cause noise to a 4-layer RF PCB?
I'm designing a 4 layer GPS tracker PCB with the 2nd layer as ground and 3rd as Vcc. Is this a good practice? I know a gnd layer is good but I'm not sure how to distribute the positive of the supply ...
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PCB multiple ground planes
I am designing a two layer PCB. Two part schematic is shown in attached figures.
In the circuit, I am getting four gate signals from FPGA of 3.3V and and error signal, also of 3.3V as inputs and I ...
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Is the bracket of a graphics card grounded?
I would guess so, but I want to make sure.
Edit: After measuring with a multimeter, I suspect that brackets (of most graphics cards) are grounded to the graphics card's ground-plane.
I measured 0 ohm ...
user127725
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Altium : How to connect pads of an F antenna
I'm designing a reverse F antenna. It is connected to ground and the antenna line.
It is built of several place fill with small overlaps.
To do this, I declared the component as a net tie. The ...
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Ground type for DC regulator
When considering a simple DC regulator such as a Texas' LM22677 on a PCB, should it use the digital or analog portion of the ground plane?
EDIT: Contextualizing, I have a 12V input feeding two ...
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Where is the ground in this circuit?
I am designing a simple digital circuit on a PCB that includes a power supply that provides +24V and -24V, but there is no ground. I am assuming that the negative voltage (-24V) is ground? What about ...
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