Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [shielding]

Questions regarding shielding devices against noise, interference, or ESD. Not to be confused with arduino-shield.

303 questions
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How to connect USB Connector shield?

How should I route USB Connector shield on PCB? Should it be connected to GND plane right where USB is placed, or should the shield be isolated from GND, or should it be connected to ground through ESD protection chip, high resistance resistor or…
Andrzej H
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Correct place to attach shields for twisted pairs

I have two PCBs connected by a cable containing 5 sub-cables: 6v power through a custom made coaxial cable (similar to that found on laptop power supplies). 2x 100mbps LVDS through 100ohm impedance screened twisted pair. 2x 1mbps CAN through the…
Rocketmagnet
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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 100mV range and are generated by very low power…
Ali
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Is twisting a single ended signal with its own GND really useful?

I know that the most robust way of transferring an analog signal over long distances is via differential pairs which are twisted together and then shielded (shield grounded at one end only). But sometimes, we have to make do with single ended…
user42875
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Shielding can, what is the proper way?

I like to protect a sensitive circuit of mine with a shield. I don't have a picture but basically, I have put together a 1 mm thick ground rectangle on the top layer, and I will place the shield on top of this such that it will contact to this…
Ktc
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Failed radiated emissions test on USB cable - USB module hardware and firmware improvements

I posted a few days about ago how our product failed ESD testing. Well, it also failed radiated emissions testing so I thought I'd make a separate post. The product is a 5V USB powered, non-radio, 3v3 LDO regulated, 2 layer PCB inside a plastic…
Geo
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Cable shielding adequate for video, but not audio frequencies

I am no expert in audio equipment, but to educate myself I have been studying. In the process, I came across a video which tests the audio frequency shielding of a purported shielded video cable. (I cannot attest to the fact that it is indeed a…
Math Keeps Me Busy
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How to Connect USB/Ethernet Shields to Chassis or Digital Grounds

I have a PCB with a few USB and RJ-45 Ethernet connectors on one side. I'm quite confused as to how exactly I'm supposed to be hooking up the SHIELD pins on them though. This is for a host device that will interface with peripherals. It is provided…
Matt
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2 answers

Grounding PCB to enclosure

I am designing a small sensor which fits into a custom aluminum enclosure. The sensor uses CAN bus and a long cable to connect it to the host and power. The shield of the cable will ground the enclosure through the connector. While developing the…
SensorMan
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Does Shielding "Electrically" shield "Magnetically" too?

I know it sounds like a newbie question but I can't wrap my mind around it. An electromagnetic field is electric + magnetic field. So this means that when shielding an equipment offensively, for example from avoiding causing interference with other…
user138887
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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 PCB that contains two USB 3.0 hub chips…
apalopohapa
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Can a shield propagate EMI?

At a job site we typically have 10 vehicles connected to a single vehicle (star layout) by a 100m 5 conductor cable carrying power(unused), ground, shield, CANH, and CANL. The shield is grounded on both ends, but the ground is effectively the…
CoderTao
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Purpose of bare copper perimiters on HF PCBs

I have seen many RF PCBs with a thick, rounded area of exposed copper going all around the PCB, like in this example: My intuitive thought is that this is for some kind of grounding or shielding can, however I have seen this on PCBs that had none…
Azsgy
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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?
aswine
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What is a more effective shield for magnetic fields between 300 and 500kHz Solid copper or copper mesh?

I am working on a PCB that is very crowded, and has high gain amplifiers working between 300kHz and 500kHz Typically I would use Mu metal or similar for shielding at this frequency, but obviously nobody makes Mu metal PCBs. So I have a choice of…
user121934
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