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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How to properly ground an old turntable and tonearm?
I have a specific question about proper grounding of an old turntable that hopefully has some general merit for such older devices.
This question came up while I was inspecting the wiring of the ...
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Shall I connect '-' terminal of power supply to earth GND (green terminal)?
Attached is the current lab setup for my chip testing. The green square represents the main PCB board, and little blue square represents the chip. The chip needs separate VDD voltage for its analog ...
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Possible ground loop trouble with detector design
I am a physics student trying to build a proportional counter. I am having huge trouble dealing with possible ground loops in designing the system.
The current design is attached below. Could anyone ...
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What is the best practice to connect isolated CANBUS transceiver with non-isolated CANBUS transceiver on the same CANBUS network?
CAN Background
According to some places, CAN transceivers do not need GND connections since the line is differential. After long research and understanding how the CAN transceiver works, GND is ...
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PCB design - noise and ground loop
I'm working on a electronic load and it's not very sensitive to noise, the questions are mostly out of curiosity.
On the PCB I have a fan control circuitry that I separated the ground and positive ...
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Preventing servo motor and drive ground loops in shielding
I have an XYZ CNC machine that has an electrical panel with industrial servo drives.
I recently had an EMI problem on the encoder cable for one of the motors, and tried to diagnose the problem.
The ...
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Guitar pickup and headphones common ground
Trying to get rid of cables on stage.
Is it possible to have a shared common ground for my guitar pickup and monitoring headphones (with a clip on headphone amp) without getting a signal loop?
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How to correctly ground/isolate a grounded enclosure type thermocouple?
My K-type thermocouple (grounded enclosure type) connected to MAX31855 adapter connected to Arduino Mega gives me faults every few readings. It's really, really bad. I've tried swapping thermocouples, ...
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Controlled impedance stackup questions
In this stackup (I know that it is not the best stackup but it is a general question,) if I choose to use controlled impedance on L4 (let's say 50 ohm), what is the ...
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How to design a schematic and PCB for an ADC using separated grounds
I want to measure a DC voltage with very high resolution (uV) and send the value to a PLC (based on an Arduino Mega.)
Initially I selected an ADS1115, but I got some power noise due to loop currents (...
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Split plane under FTDI pads USB 2.0
I want to ask you if its a critical issue
Differential signals from usb 2.0 (DP,DN _ 90ohm) routed to FTDI device FT4232HL
the pads of FTDI IC(1.58mm) goes under a split plane (the marker signals are ...
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Crossing power (ground) domains on a PCB with a digital signal
I have a circuit with a common battery "ground" and a few non-isolated voltage regulators. In order to minimize electrical noise on the printed circuit board I've taken care to maintain a ...
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Do ground loops matter with the Pi Pico?
The Pi Pico's pinout contains multiple ground pins:
My understanding is that this will create ground loops where current can flow.
Is this a problem? Should I only use one of the ground pins?
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How to interface Raspberry Pi 3B+ with peripheral board from different power source?
As I mentioned in my question, I have an IO controller board with many digital/analog IOs, ADC IC and many relay units. It gets its power supply from a 12 V 5 A SMPS. The board has its own buck ...
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Maintaining voltage on PCB track
Suppose there is a really long track (not infinite) running over a 2-layer PCB with the bottom plane being the ground plane (just to complete the reverse path of the current). Now, on one end, 5V is ...
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Having multiple ground connections
When and where should grounds be connected togheter?
I am currently in the process of designing a product as a hobby project. And i find myself getting stuck with (probably) a rather simple question.
...
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Doubt about grounding loop and shielding
Good morning,
first at all I want excuse me for my english and my inexperience.
I have working with complex setup (osciloscope+SMU+Waveform generator+ some circuits and shielding cage) and now Im ...
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Can I power a router, some HDDs and a Raspberry Pi4 from the same power supply?
I want to build a kind of NAS. See the plan in the picture below.
Is it ok to power all the devices from the same power supply? A friend of mine warned me that it might not work because of the so-...
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Isolated DC-DC converter
We have a design in which we need to isolate a communications signal coming from a TTL serial port and going to a DUT sitting on a bed of nails (functional tester).
The supply voltage ranges from 2.5 ...
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Potential static fault on chassis of system
The image attached is to demonstrate the observed behaviour. As the robot nears the push pads to charge, it moves its actuators down to make contact and as the contact is made the internal computer ...
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Power return and grounding - Is there a right way?
I'm currently designing a multi-PCB system with many power rails and return paths, but I'm not sure if keeping power rails isolated and only linked together on the PCBs is better from a noise/ground ...
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Understanding why daisy chaining causes ground loops in this setup
At this site, the star connection is recommended for daisy chaining. And in that context, it is written that one of the benefits is less ground loop effects.
This ensures each device will have the ...
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Successful high voltage (400 V DC) measurement with isolation
I want to make a precharge system for an electric car for which I require voltage measurement.
Here is what I am doing:
Stepping the voltage down through voltage divider (0-5 V) range (high side).
...
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HDMI ground loop from gaming PC to AVR
I have a ground loop from my HDMI from gaming PC to AVR. It's very annoying.
Aside from getting an expensive ground loop isolation transformer for 1000 W, is there any other way?
Is there an HDMI ...
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Ground loop impedance when measuring pH of salty/conductive liquids
I have a reservoir of conductive liquid (~2000 μS). Inside that liquid are two sensors: a pH sensor and a conductivity cell.
The conductivity cell is a two-terminal device and submerged. When ...
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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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Why is single-point series grounding avoided in resolving ground-loop problems?
It appears that using single point series grounding, there is some additive effect
$$
V_{c}-\mathrm{what's\;accounted\;from\;Circuit\;1\;and\;2}
$$
My question is if this approach is closest to what ...
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common ground issue in signal transmission?
I am designing a device that output analog voltage in the range of -5 V to +5 V representing a certain measurement (single-ended earth grounded). My plan is to use a regular BNC cable, (earth ...
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Can I use 2 different power supplies to power the electret mic and op amp separately?
the power supply is a placeholder and it will be rated 12v to power the ne5532 op amp since 5v cannot power the op amp. The 5v dc will come from the same usb as the sound card which the electret mic ...
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Can a ground loop occur if everything is sharing a single socket?
In a system where all devices that are connected ultimately share the same wall-socket, is it possible for a ground loop to occur.
For example:
A strip cable plugged into a socket powers a computer ...
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Could the grounding of this circuit cause any issues or be improved?
These two boards are supplied from a 24 V power supply like in the picture shown. I didn't design any of them. The first board cannot be modified at all, the second board can be modified completely. ...
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Use TRS jack as Mono + 5V power input
I'm trying to change this guitar wireless transmitter so that the audio input jack also becomes a charging/power source.
The charger will be a separate box with "stereo" input socket.
...
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How did using the shield as signal return end up as a common practice in audio?
Or in short: was cost the only motivation? Because the major reason against this practice must have been already plain obvious in the mid of last century.
Namely, using the shield of a cable as signal ...
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How to implement a ground loop isolator in an audio circuit that connects to USB and line out of a laptop?
I'm working on an audio interface that utilises a microcontroller and a CS42448 audio codec. When receiving USB power and receiving audio from a laptop, there is a ground loop. Otherwise, it works ...
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How does the current of RS485 signals return from the receiver to the sender?
I am planning a system consisting of 1 master device which is connected to 19 slave devices using RS485 transceivers. Also, all devices are powered by 1 PSU. A simplified schematic is shown below.
As ...
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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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Ground loop between two devices powered by the same power supply
I'm working on a project with a Raspberry Pi and a Bluetooth receiver which are sharing the same ground and the same power supply.
The wireless receiver gets the signal (audio content) and sends it ...
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Isolated DCDC converter bonding to ground
Is it okay to short input and output negative terminal of an isolated DC-DC converter? This kind of situation is not mentioned in the datasheets. The problem arises when a load has negative terminal ...
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Single Ended Signal Ground In a Loop
I have ten devices that I need to connect in a loop so they can send data from one device to the next until it returns to the original device. The devices are about 5 inches apart.
They are all 5V ...
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Why does analysis indicate that ground lifts do not fix ground loops?
Note: "Ground loop" in this question refers to a ground loop caused by linked magnetic fields. (Sometimes ground loop refers to slightly different scenarios.)
Recently I've been looking into ...
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Can bussed grounds in an audio patchbay create a ground loop?
I am working on a project to create a patchbay-style interface for guitar pedals, wherein a set of guitar pedals can be routed in different configurations using TT cables (like the patchbay interfaces ...
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Grounding concept for an electrical machine test rig
I'm tasked wich building a test rig for electrical machines which consists of
Machines mounted on top of a large ground plate which is connected to PE through a thick cable
A torque transducer: The ...
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CAN bus ground wiring
I am trying to create a concept for a system containing a 36 V battery, a 12 V battery, an Nvidia Jetson AGX Xavier, a CAN transceiver and two motor controllers.
I am struggling to make the correct ...
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Voltage difference between grounds
I built the following circuit on a breadboard
There are two power sources involved in the circuit, one for the Arduino (5V) and the other is the battery (3.5V) and all the components share a common ...
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RS-485 Connecting 100 devices - Avoid GND Loop
I'm new to community and it's my first question, so please forgive me for mistakes I could do referring to adding pictures and descriptions.
I plan to use 100 devices and connect them via RS-485 in ...
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Noise from switch mode power supply and ground loops
I've got a piece of equipment that has pretty severe noise on it that I'm trying to improve. It's an older system (built in '96 but a lot of the design is probably late 80's) and is mostly bundles of ...
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Isolated balun questions
Please see this diagram:
On the left is a fairly typical unbalanced to balanced circuit featuring 2 opamps.
The signal is then passed over a shielded twisted pair.
On the right, I want to use a ...
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How to mitigate an unavoidable ground loop in a vehicle?
We have a display and a sensor that are installed in vehicles. The sensor is in a metal TO Can, and the manufacturer shorts the ground pin to the TO Can body for shielding. We mount that can in a ...
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Avoiding ground loop through d-sub like connector shield over metal enclosure
I have to pass a couple of analog signals between separately grounded systems over a HPDB68 cable. Ground loops have been a major issue previously, so the signals are passed differentially and ...
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Instrumentation Amp design for breaking ground loops between systems
We're in the midst of designing a device for measuring analog signals and have been testing our initial prototype. We had a single-ended gain stage before the ADC, but due to the connections in the ...
