Questions tagged [grounding]
Problems related to the connection of circuits to ground or earth references. Can affect safety, accuracy, reliability and interfacing.
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Analog & Power Ground Planes Doubts
Working on a new board, I have to face some requirements to ensure the performance of the whole system once is manufactured.
PCB is a 4-layer one, and it has both analog and digital components. But ...
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Should chassis ground be attached to digital ground?
I'm working on a PCB that has shielded RJ45 (ethernet), RS232, and USB connectors, and is powered by a 12V AC/DC brick power adapter (I do the 5V and 3.3V step down on board). The entire design is ...
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Why don't we use neutral wire for to ground devices and earth wire for closing the circuit?
I know that the neutral point of a distribution transformer is connected to the grounding (earthing) wire, so I think they are the same.
Can I use the neutral wire for protecting metal-cased electric ...
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Why on earth are o-scopes earth referenced?
Thinking about it: You would never find a "Grounded" multimeter as robust and useful if a path to ground through the multimeter were introduced, modifying the circuit's behaviour and possibly damaging ...
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Competing PCB Crystal layout recommendations
This is related to this question: How's my crystal oscillator layout?
I'm trying to layout a 12MHz crystal for a micro controller. I've been reading through several recommendations specifically for ...
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Is ground connection in home electrical system really necessary?
I know that the answer to my question is "Yes, it is!". The ground connection is needed to avoid a person touching a metallic part of faulty equipment to be electrically shocked. So the ...
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Reason of multiple GND and VCC on an IC
What is the reason that most of ICs (e.g. MCU) has multiple (A/D)GND and (A)VCC pins?
If it is to increase performance of an IC, how does it help to performance? or is it easier for the IC designer ...
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USB 3.0 Hub shield connection
This is about the seemingly controversial shield to ground connection. The system is basically a body-worn intel-based computer, powered by a battery. Two USB 3.0 (or 3.1 Gen1) cables come out to a ...
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How should I connect AGND and DGND
I have been reading about grounding in a mixed signal systems. Do I get it correct that it is best to group analog and digital elements and then have a single ground plane, as long as the digital ...
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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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Why does connecting a high-current device to my digital circuit cause weird behavior?
I have a
arduino
microcontroller
other digital thing
and when I connect a
motor
pump
heater
other high current thing
I experience
weird ADC measurements
reboots
crashes
errors in digital ...
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Why is there a 0R resistor linking GND and AGND in analog voltage reference circuit?
This is related to another question I've just posted (What's the purpose of a ferrite bead inductor on this circuit?), regarding the battery charger described in the AVR450 Application Note - ...
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When does and when doesn't current flow to ground?
I was thinking about when current can and can't flow to ground. I came up with that current will only flow to ground when we have at least two grounds in the circuit, since then we have a complete ...
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Anti-static mat connected to earth directly or 1E6 ohm resistor?
Should an anti-static mat be connected to earth directly or with 1E6 ohm resistance in between?
2 layer mat. Upper side: dissipative (10E7 ~ 10E10 ohm/m²). Bottom: conductive.
To be a little more ...
user127725
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5
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Professor said no current flows to ground
According to the professor, adding the ground at 0V has no effect on the current flow and current flows in this circuit as if the grounding point did not exist so the answer is E.
How have people died ...
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Why is neutral wire connected to ground at the transformer?
I understand the use of ground wire at the home appliances but why is the neutral wire connected to ground at the transformer? Why doesn't the neutral wire go back to the power generation plants.
I ...
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How to remove noise in ADC voltage measurement?
I want to measure the open circuit voltage of a battery cell (differential reading, that is A0-A1). In order to do that, I am using an industrial PLC based in Arduino Mega and a cheap but accurate ADC ...
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Sending ground along with digital connections between boards
I have been wondering for quite a while whether it's good practice when connecting two boards together (powered from the same power supply, although each has its own regulator) to send ground ...
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10
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Why is an Ethernet cable not grounded?
There is no dedicated GND in the classical Ethernet 8P8C ("RJ45") pinout.[1]
Why does the Ethernet spec not include a ground, unlike many other cable types used for interconnecting devices that may ...
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How to safely ground a switching power supply with floating outputs?
I just received a 120VAC to 5VDC (20A) switching power supply (the kind with a passively ventilated metal casing) for use with a microcontroller project I'm working on (driving long LED strips).
I've ...
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How a person standing on a floor tile and holding a live equipment can complete the circuit?
Can someone please explain the how grounding / earthing to prevent a person from getting electrical shock using simple illustration of a faulty electric iron connected to the 240VAC mains?
I don't ...
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4
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Is a ground/common needed for proper CAN bus communication?
Since CAN Bus is a differential signalling system, what is the significance of GND/COM signal? Can I get by without it?
I've got a very simple 2-node system that has some weird happenings going on. (...
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Single point vs Ground plane, in audio OP AMP PCB layouts
Recently I had posted a seemingly innocent question on another forum. I was trying to keep a small and relatively simple circuit down to a 2 layer board and was asking about the shielding merits of a ...
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Portable device shielding & ESD
I'm working on a portable battery-powered device with a shielded I/O connector for sensors, but I'm confused about how to properly ground the shield and ESD array. Here is a block diagram of my ...
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How to add ground to DC circuit?
I'm just a dabbler in electronic circuits and I'm really still kind of a noob. I am working on a project called the "Atari Punk Console" (Originally known as the "Stepped Tone Generator") but there ...
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Kirchhoff's Current Law at the ground node?
Can one do KCL at the ground node? Does any current go into the ground?
I think not, but I am not sure.
Bonus Question:
If yes, then how does grounding buildings drain the current into the Earth?
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Why is main's neutral tied to earth?
My dad is an Electrician and I myself am an Electronics Design Engineer, and to this day he still hasn't been able to give me a good reason for this.
Consider the two following pictures/situations - ...
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Is it a bad idea to plug the other end of ESD strap to wall ground?
I have gone through this answer on Superuser, while it provides good information, I still have a specific question from electrical/electronics engineering point of view.
Is it wrong and unsafe to ...
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Noise reduction strategies in electrophysiology
When recording electrical signals from cells (in a dish or inside a living human or animal body), one major problem is to increase the signal to noise ratio.
These signals are usually in the 10uV to ...
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Why the arc when bonding-on during high voltage repairs?
When working on high voltage power-lines via helicopter the technician will "bond-on" with a steel wand called a hot-stick. During this process an arc is conducted from the line to the wand. Now, ...
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When to use ground plane cutouts?
I've been reading more about proper grounding techniques and using ground planes.
From what I've read, ground planes provide a large capacitance with adjacent layers, faster heat dissipation, and ...
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RS485 network ground pin - when to connect?
As many know, one can implement a simple node to node rs485 communication by using only two wires, A and B. Well, the standard specify to connect the ground of the two node together.
from Wikipedia:
...
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Grounding and why charge leakage occurs
A basic nugget of info is missing in my end-to-end picture of how grounding works and why it's important. When a voltage is applied in a circuit the electric current starts flowing (or the field ...
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Does an ungrounded shielded cable shield at all?
Does a shielded cable provide any shielding if the shield isn't grounded? Would it be practically different than an unshielded cable?
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Grounding of ADC grounds
Fast, high resolution ADCs, especially ones that have parallel output, usually have a separate supply pin (DRVDD, (drive vdd) or OVDD (output vdd)) presumably because they don't want to couple noise ...
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Grounding Metal Object to Eliminate Static Electricity Using Electrical Ground
let us say that I have built a metal cabinet in which I will be painting small objects. I am looking to eliminate any static electricity that could possibly build on the object to be painted or on the ...
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Why do some devices have 200V on the case?
I recently got a desktop LED lamp, and I feel a "strange" slight vibration when touching the metal case. I found that other devices also have high voltage on their case.
What is the reason/trade-off ...
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What is signal ground
I encountered signal ground symbol while studying 555 IC
Please explain why isn't a simple ground connection used and how does signal ground differ from normal ground. I am a first year undergraduate, ...
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ungrounded chassis shielding
I'm looking into whether an ungrounded metal box provides good/bad EM shielding.
This thread seems like a definite "good", for reasons of the box acting as a faraday cage : How much shielding does an ...
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2
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How does Hybrid Ground Works?
The text that is above the figure is from my textbook and i am having difficulty to understand what it is trying to say because it's not in detail!! why only remove high frequency and prevent low ...
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votes
1
answer
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Why does my TS101 soldering iron turn on LEDs upon contact?
An LED on my board turn on and stays on when I touch it with my soldering iron and it's freaking me out. This happens even though the board is just sitting on my (wooden) desk and not connected to ...
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2
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USB shielding, device or host side?
I have an SBC with a USB host port, but it is exposed as male header pins rather than a female USB port.
I have soldered female headers to a USB cable and have a working but intermittant connection, ...
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2
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Grounding a laptop through the DC-jack?
I would like to reach zero potential difference between me and my laptop
(to avoid ESD) before opening the back cover.
I'll connect my wrist strap to a common ground point, thru a resistorized coil ...
user127725
2
votes
1
answer
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Using aluminium enclosure as heat sink
Can I use the aluminium enclosure of my mains powered product as a heatsink?
I'm thinking about mounting TO-220 transistors pressed against the enclosure, to get away with passive cooling by using ...
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2
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4
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Why earth ground connection does not leak current?
This seems like a question which has been asked multiple times on forums. I researched the problem but I still was unable to figure out the answer which I can at least intuitively understand. So in ...
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Does electricity always flow in a closed loop and why does current flow to ground?
I have been taught that current flows in a closed loop back to the source. And with electrical distribution, current flows to ground because the whole grid is effectively grounded back to the source. ...
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0
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Connect Arduino to existing circuit with seperate power supply
I have an existing closed system that exposes several inputs that I would like to drive with an Arduino. The existing system (Neptune Apex Controller with break out box) is designed to sense the ...
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3
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Why do I have 44V AC between ground and the V(-) and V(+) of a switch mode power supply?
I have a system were we wish to place a USB charger outlet. The output is placed in a bench made of metal, so even if the output is isolated and low voltage, it would be a good idea to ground the ...
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How to split Analog and Digital GND planes for a TQFN device
This question is in reference to Mixed signal PCB layout for PSoC.
If I am using a microcontroller which has separate analog and digital supply inputs and GNDs, what should do with the grounds?
...
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0
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Subwoofer hums when no audio source is connected [closed]
The hum stops as soon as an audio source is connected or any metal part of the subwoofer is connected to the ground of a socket.
Does anyone have any idea what the problem is?
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