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 does star grounding work when you include a chassis and multiple PCBs?
I am just wiring a project and I was wondering how the star topology for LV grounding works when using a chassis GND as well. I have a metal enclosure which houses a few electronic boards. One master ...
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RP2350 or RP2040 Power Setup
I want to create a board ideally using the RP2350 (if they're able to release for industrial and academic purposes by the end of the year) or the RP2040 as a microcontroller for a custom board. I need ...
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Edge ground loop on a PCB
I recently added a ground edge on my PCB to reject EMI noise on. Adding this ground loop have a strong effect on rejecting EMI noise:
My PCB is a 12-layer board, currently I have this ground loop on ...
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Connecting a transimpedance amplifier powered by an isolated power supply to a grounded digitizer?
I've recently been assigned to a project where we are sensing changes in the current passing through a biological resistor, and these changes in current are on the order of nanoamperes and on short ...
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Potential ground loop issue in DC-DC common ground circuit
I am trying to setup a dedicated battery for my dash-camera, this will provide continuous power when the ignition is OFF and has a manual NC switch to turn off the circuit when not needed.
I ...
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Isolated DC-DC converter Baseplate grounding
I am planning to use an isolated DC-DC converter from VICOR to create two ground reference for the input and output side of the converter for a circuit requirement. The input and output pins of the ...
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Common Ground Issue for the System
I am facing an issue with my common ground for my system.
The system below has a voltage of the battery equal to 16 V and the power supply is supplying my MCU with 3.3V and 0.20A.
What is the ...
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Ground loop issue with Raspberry Pi and amplifier board
I'm trying to run a Raspberry Pi with a USB audio adaptor into an external amplifier board via 3.5mm, then running out to speakers from the amp.
Right now I'm getting a lot of electronic noise coming ...
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SPI cable with twisted pairs with ground: Are ground loops an issue?
I am connecting my microprocessor to a SPI device through a cable, with the SCK, MOSI, SS and MISO lines, in addition to +3.3V. I was told it is advisable to twist each line cited above, including the ...
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Flickering on LED strips routed through buck converter and slip ring
I am building a totem for a music festival that consists of three rotating rings covered in addressable LED strips. Each layer is connected to the one inside it via a servo on one side and an ...
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Stepper motor noise
I’m currently developing a belt drive system that uses two separate Nema 42 stepper motors and an htd pulley. Everything is working well except I recently increased the supply voltage from 110 to 220 (...
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A 10cm long trace runs through the middle of a 2 layer PCB and cuts the ground plane in half one one layer. How to prevent this?
Basically, my PCB has one side that will be facing an enclosure's panel with IO. This side has a slide switch that needs to power a 12V power relay that draws 37.5mA when turned ON, but is located in ...
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Half-bridge driver ground loop elimination
I built this half-bridge driver using a generic Schmitt trigger/hex inverter IC and a 555 timer as the square wave generator. By varying the value of the resistors, the dead time can be adjusted and ...
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Balance Mic and Speaker for Camera Input with Ground Loop Isolation
Novice looking for some help.
I use a Cardo Bluetooth headset to communicate with friends and record the audio onto an action camera while out riding motorcycles. By trial and error I was able to come ...
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Should two different DC power supply GNDs be connected to each other on a PCB?
I'm making a small project that drives a few DC motors with H-bridges.
+12V DC will come from one DC power supply (regulated to 10V for motors,) and then +5V will come from another (different) DC ...
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Grounding in power electronics
I'm designing a three-phase inverter and have been looking up information online with respect to grounding, which led me to a somewhat misapprehension.
In my system I firstly planned on separating the ...
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Ground loop with oscilloscope probes
I am trying to better understand how ground loops affect a circuit and why it is important to do not have ground loop on a circuit. So I am trying to look at systems with ground loop to further ...
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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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Changing grounds during start up
We have a system with a CANBUS controlled Battery Management System (BMS) and a PCB with microcontroller. The BMS provides 12V and an isolated CAN ground at all times, but naturally only supplies main ...
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Should I ground a sensor locally or at the microcontroller input?
If I had a sensor with an analog voltage output (temperature or pressure with slow sampling rate) and a common chassis ground available (like a boat, plane, or car), should I ground it locally or at ...
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Connecting '-' terminal of the power supply to the earth GND
I've already asked a similar question in the past, but I want to make sure I understood things correctly.
Attached is the current lab setup for my chip testing. The green square represents the main ...
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50 Hz noise on INA125 for Wheatstone bridge application
I am trying to measure mechanical deformations using a full Wheatstone Bridge.
In order to do that, I connected the bridge to an instrumental amplifier (INA125PA).
The amplifier is powered with a dual ...
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Can the 5V and the 12V rail on a PC PSU share the ground pin? Proprietary -> standard ARGB fan connectors
I use 6 PC case fans which I want to get out of their proprietary 6pin connection.
They are made by the budget fan manufacturer Asiahorse and connect to one of their hubs right now. But the topic ...
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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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