Questions tagged [ground-loop]
For questions about ground loops, which occur when multiple ground nodes in a circuit (which should be at the same potential) actually have a potential difference between them. This is usually caused by a significant current flowing between the ground node(s), thus producing a voltage between them. Ground loops cause various problems in a circuit.
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Ground loop? Switch mode power supply noise
I have a single 12V supply powering a 12V class D audio amplifier (Tripath TA2020 based, model 'SMSL SA-36') (C) and a very cheap 12V to 5V 2A rated switch mode converter (A). The 5V is used to power ...
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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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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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Power supply noise in audio
I have what is surely a classic problem with regard to power supply switching noise and audio but I am unable to sort myth from reality with regard to what I found so far on the topic.
Setup:
I have ...
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Isolating audio ground between devices
I'm planning a build for a guitar amplifier with 2 stages, the first being a tube pre-amp and the second stage being a solid state amplifier. Both amplifiers will be powered from the same source, a ...
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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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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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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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Understanding ADC digital isolation to avoid ground loops
I have designed a circuit to measure the voltage of a battery. This battery is being cycled all the time by a potentiostat (charging-discharging) which injects positive current to charge the battery ...
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Why is this resistor connected between connector shield and ground?
I was looking over my raspberry pi model B and I noticed a resistor between the USB power connector shield and ground. I've noticed this on many PCB designs with much larger packaged resistors ...
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Can I use ferrites for the ground connections?
I may have an issue with conducted EMI through the ground connections between devices in a system. There is specifically a device which clearly creates noise on the measured signal from another ...
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For Multiple ADC circuits PCB layout grounding, why is "single point ground" important?
I am reading this article from Maxim on mixed-signal circuits grounding:
https://www.maximintegrated.com/en/app-notes/index.mvp/id/5450
Everything makes sense to me until I read the "Grounding ...
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Ground Loop Explained
I need somebody to explain properly how the ground loop works, especially if this happens when is only a DC circuit like a power supply for a motor and a coaxial cable which carries a PAL signal. ...
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Ground loop when measuring in process pH
I have been experiencing a very difficult to solve ground loop problem with my pH measuring system. My basic setup is a standard pH electrode running through an op-amp to an ADC which communicates ...
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Ground loops with balanced connections?
Different articles and tutorials provide somewhat contradictory information about ground loops.
For a balanced (differential) connection, the return path is "the other wire" in the ...
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Monopole antenna: does current flow in loops?
I've been wondering for the longest time about how a monopole antenna (like the one in a typical FM radio) can work without offering a return path for current.
I have a hypothesis, and I'd really ...
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How to share ground connection between to microcontrollers connected to a PC
I have 2 microcontroller evaluation boards and I am trying to make a I2C communication between them.
Both of the boards are connected to the same PC using USB cables. SDA and SCL pins are also ...
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USB port and bench power supply ground difference
So I recently coughed up the $250 for a semi decent bench power supply, the thing that got me though is when powering a circuit from this unit and connecting the BusPirate via USB is that the ground ...
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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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Which one of these shielded scenarios is correct?
I have a system were both the signal generated and the sensing equipment is sharing the same ground.
Which one of these shield terminations scenarios is correct? (if any). I searched the internet for ...
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Optocoupler to switch 24V using Arduino
I am currently redesigning a circuit to switch a spring applied brake using an Arduino Micro.
The current circuit looks like this (please excuse if I'm using wrong symbols, I'm learning by myself):
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Buck Converter PCB Planes
I have a question about PCB copper planes with buck converters. For reference, I'm using the LM2673/LM2679. The parts are identical in layout, utilizing the DDPAK/TO-263-7 with the PCB tab being ...
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Grounding Neutral Off Grid Solar
Is it recommended to ground the neutral line in an off grid solar system?
A nonisolated inverter would be by definition wired this way, right?
I believe that in home electrical systems neutral is ...
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Using an earthed function generator with an earthed oscilloscope and ground loops
I have a function generator and I noticed that its DC GND is internally wired to its earth pin.
Similarly I have an oscilloscope and I noticed that its DC GND is also internally wired to its earth ...
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Why is ground meaningless in high speed circuits whereas more important is the path of return current?
I know everything about this topic but I don't know why ground is meaningless in high speed circuits. So basically in high speed circuits these are the factors we need to consider-:
Decoupling caps
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Connecting Two Grounds Together
I'm trying to understand what would happen when connecting two grounds from diffident power supplies together. A more in depth explanation of what I'm trying to accomplish is here: Connect Arduino to ...
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How can I eliminate the loop in this diagram?
I'm really sorry to open some series of questions but since the issue is complicated I decided to open a separate question for a particular thing for not creating confusion:
There is the red loop in ...
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Ground loop isolation of a USB-powered device
I have a device (Device 1) that is bus-powered via Full-Speed USB and that is drawing up to 400 mA from a laptop.
Device 1 has a DAC that can output an analog voltage to another device (Device 2) ...
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Multiboard Grounding In High Frequency
How can ground loop be avoided when connecting two system with same ground. This happen in PC with SATA cable or PCIe Card with separated power cable.
My System
Board: I have two pcb each with a ...
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What options are available for measuring grounded thermocouples?
I'm using 4 MAX31855 ICs to measure 4 K-type thermocouples and realized that 2 of my thermocouples have grounded junctions; I simultaneously also realized the MAX31855 is stated to not support ...