Questions tagged [esd]
ElectroStatic Discharge, it's caused by accumulation of electrostatic charge as a result of rubbing, and can damage semiconductor devices like integrated circuits.
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Alternatives for routing two pinouts to the same RJ12
I’m working on a project that is basically UART, power and a couple of I/Os over a RJ12 connector.
I want to be able to interact with two different devices that have the same interface but with ...
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Correct way of optical input EMC protection
I tried to find an answer online, but didn't find anything that would make my doubt go away.
The thing is: when you want to protect any input, that is referenced to ground, you use ground-referenced ...
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Is a 3D printed motherboard case ESD safe enough?
I am developing and 3D printing a case for the development boards (PYNQ) we use at our university. However, I have read online that PLA is quite bad for ESD protection. I found products for anti-ESD ...
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Unidirectional or Bi-directional TVS diodes - Which one to use?
I would like to understand in which places one should be using a unidirectional TVS diode and a bi-directional TVS diode.
In the USB power line, VBUS (5V), is it enough to place an unidirectional TVS ...
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Ethernet PHY ESD protection, difference in components
I'm using a Würth Elektronik 7498210220A jack (datasheet) and I need to add ESD protection to TD and RD lines of this Ethernet connector (with integrated magnetics).
Application of this Ethernet ...
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Why use a steering diode with a TVS for ESD protection?
Take this SR05 for example. The data sheet explains that you can use it with or without a reference voltage at pin 4. So why have the steering diodes at all for ESD protection? Is it to ensure that ...
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USB ESD Protection with the NUF2042XV6T1G IC
I have been trying to figure out how exactly I should connect the NUF2042XV6T1G IC to my USB data lines. From what I understand, usually a reverse biased transile diode is connected between the data ...
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USB Port Design with ESD/Overcurrent Protection
I am working on a small project in which I use a CH340 to communicate with an MCU, but during prototyping I probably should have a way to protect the controlling computer's USB port from shorts. I ...
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Separate ESD traces/layer?
I am designing a keyboard that connects through USB-C to a computer and has Aluminum chassis. I am dealing with ESD protection for the enclosure itself and some exposed components (that have a "...
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Question of Ethernet PoE and TVS protection [duplicate]
My question is based on this question over here
Asking this question here since I didn't receive a clear answer that clarified my confusions on TVS for PoE applications.
As far as I understand, the ...
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USBLC6-2P6 - does the direction matter?
I'm designing a simple PCB with STM32F4 MCU and USB, and I want to use USBLC6-2P6 for ESD protection. However, using the EDS protection device as presented in the datasheet creates the need for me to ...
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Does this circuit have a good enough ESD protection to protect I2C line or do I need a series resistor?
I want to be able to run a wire to an I2C device as far as posible for learning purposes, but I also want to know how to protect the I2C line from ESD events to exceed level 4 of IEC 61000-4-2.
I am ...
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I'm making a development board for ESP32 S2 board, I want to achieve IEC61000-4-2 (level 4) ESD protection on the connectors
I am using a 4 channel TVS(diode) array that has a max clamping voltage of 12V. I have a voltage devidor to translate 5V to 2.5V. So I asume that max clamped input is 6V if an ESD event occurs.
I read ...
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How should I select appropriate capacitors to ensure compliance with IEC/EN 61000-4-2:2009 and IEC/EN 61000-4-5:2014 standards for my device?
When applying the IEC/EN 61000-4-2:2009 and IEC/EN 61000-4-5:2014 standards for our device, our consulting firm recommended bypassing the input power jack to the chassis ground using two 33nF ...
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Why clamping voltage is not given for some ESD diodes
I was comaparing two ESD diodes.Their P/N's are PESD5V0S1BL,315 and
PESD5V0U1BL,315.
If you check the datasheet of both parts you can see that clamping voltage is specified for PESD5V0S1BL,315 and ...
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Weird pinout of USB ESD protection
The USB ESD protection component USBLC6-2SC6 seems to be very popular (?). However, its pinout seems not ideal:
The USB differential pair should be routed close to each other, but the pinout of ...
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CPU's ESD Rating
Today I was assembling a PC, and went through all the ESD stuff but at the end was wondering how sensitive are these devices actually are. So my question is
What is the ESD HBM rating of a CPU pins ...
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Overvoltage Clamping protection for Boost Converter
I think my circuit is failing because of ESD and/or transients when initially connecting my device to a supply. How should I go about protecting the gate of M1? What's the best way to clamp the ...
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Problems with USB port and Littlefuse ESD protection on ESP32 and Mac
I needs some help for select/wiring USB 2.0 port, which is for ESD protection.
should mention that I'm not that much experience with ESD before, so google it and finally choose littlefuse lineup.
As ...
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What will happen if I choose a higher value capacitor for ESD protection than the recommended value?
I want to protect my circuit from ESD, for which I have chosen a capacitor as ESD protection due to size and cost.
I have chosen a KEMET 1000 pF 16V with 25 kV breakdown voltage capacitor value ...
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Selection of ESD diodes
My objective is to protect the pins of a device.
The pins are connected to an external connector which might be exposed to an ESD event.
Hence, I need to place an ESD protection device on that line.
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Suggestion for ESD Chassis Ground for Battery-Operated Device with Plastic Enclosure
We are developing a wearable device that is battery powered which is enclosed with a plastic enclosure. As a requirement for safety, we submitted the device for EMC testing, which includes Indirect ...
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Cable / Device Shielding
Is it required to connect Shield cover to the enclosure at several points in a defined way? I am doing EMC simualtion related to this and not sure on what changes I can make.
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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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Why doesn't ESD cause a large amount of current?
It is agreed that ESD is caused by kV level large potential differences:
When we handle an ESD sensitive device such as a MOSFET or a type of diode etc., why doesn't it burn when it gets damaged by ...
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Protecting from ESD only with resistors and BAT54
I have a device with too many external contacts exposed to ESD, I search for a way to reduce cost of ESD protection.
According to datasheet BAT54 can stand 1 A non-repetitive peak forward current. So ...
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How should I ground the case in a hand-wired keyboard?
I'm planning on building a Dactyl-Manuform, a type of keyboard. Often the electric components touch the external case (in some instances because the case becomes part of the means to support things ...
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Utility of shielding a laptop SSD with conductive foil -?
I recently replaced the factory SSD in my Thinkpad X260. The factory SSD came with one side covered in conductive aluminum foil which is grounded to the chassis via the caddy-screw attachment. The ...
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ESD Current path flow on this Diagram
I was reading about ESD diode arrays and protection devices and saw this question over here.
My question is:
In this diagram below, can someone help me to draw/identify the path of current flow ...
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Questions regarding ESD protection
I have a couple of questions regarding the Basics of ESD.
Usually, when we employ ESD protection, say placing a TVS diode on the signal line, the other end of the ESD diode terminal:
a) Will be ...
user220456
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Can an ESD wrist strap protect you from mains voltage?
I've watched the recent video of LTT with ElectroBOOM (The SCAM of Wireless ESD Straps - Feat. ElectroBOOM) and they mentioned that the ESD wrist wrap is essentially there to protect you and the ...
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Ethernet ESD layout
I need help in the layout of an ethernet interface (ESD protections + RJ45 connector).
The connector I would like to use already has built-in magnets, so I only have to connect the ESD protectors.
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ESD Voltage for diode - Positive and negative transients
While selecting ESD protection diodes for, say, ethernet or usb datalines, we usually select the clamping voltage of the diode more than the working voltage of the signal lines and lesser than the ...
user220456
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Possible ESD damage on UART pins between nRF52840 and ATmega1284P
I have devices operating from 2S Li-ion battery (max 8.4V).
They consist of 2 PCBs - the first one contains a 3.3V voltage regulator and an ATmega1284P, while the second one has MDBT50Q-U1MV2(nRF52840 ...
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Protect Arduino components from ESD damage from external input
I have an Arduino Due project that senses voltages through an ADC (ADS1115). The ADS1115 voltage sensor inputs will have intermittent connections. I have already fried my compass module by ESD and am ...
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Can swap trace layout of differential pair through TVS/ESD component?
Im using 2 x TPD4EUSB30 to do TVS/ESD protection for the 4 differential pairs for a RJ45 ethernet jack. To make some upstream routing a little easier I want to swap D1- and D1+. Looking at the ...
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ESD models - CDM and MM
I am just trying to understand the differences between the ESD models in this article.
The CDM and MM models are very similar. Is the MM model the reverse of CDM model.
I have this confusion as CDM ...
user220456
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Position of TVS diode in Ethernet application
I'm going through this appnote.
My question is based on Figure 1 on page 1 of the datasheet.
Am I correct in understanding that it is not correct to move the TVS diode (DBI) from the PHY side of the ...
user220456
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ESD safe soldering without PE
I live in a very old house that has no PE in it, so I can't ground the tip of the iron and myself as I should to solder in a ESD safe way. Is there any method to improve ESD safety of soldering, when ...
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What is wrong with my ESD discharge simulation circuit?
I am trying to duplicate the results given at the following URL in Qucs-s with ngspice.
https://www.youspice.com/simple-spice-esd-generator-circuit-based-on-iec61000-4-2-standard/
I must be doing ...
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Question on the USB connector shileding
I have a USB microphone, based on cm6533 chip, that appears to be in working condition, with the exception of it's fried USB type C connector. Upon closer inspection this is the circuit that houses ...
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Parallel RC circuit for chassis GND and digital GND isolation
In our design we've used a parallel RC circuit for chassis ground and digital ground isolation
The resistor value is 100 Ω. The capacitor is 1000 pF 4 kV.
I was told that it's basically for "EMI,...
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Protection for PCB inputs and outputs - ESD, short-circuit, EMI
I have a pretty simple board that wires together an Arduino and a screen. It has 3 terminal blocks - power, optical encoder, and stepper outputs (just signals).
Stepper and encoder signals are in the ...
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Connecting digital ground and chassis ground
I have an Ethernet connector whose chassis or shield ground I need to connect to the digital ground. I read that it is a practice that is followed in many designs.
My questions:
Why should they be ...
user220456
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Isolation distance between tracks with focus on ESD
I am working on a product which has to meet:
8kV IEC 61000-4-2 contact discharge
4kV IEC 61000-4-4 transients
1.2kV/500Ohm IEC 61000-4-5 Surges
The schematic:
simulate this circuit – ...
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Protecting multiple MCU digital inputs from high voltage / ESD
I need to design a circuitry with at least 16 inputs used to capture low speed digital input signals (such as buttons with dry-contact). I'm also planning to use a multiplexer/demultiplexer (such as ...
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Besides the matting, what materials are best for an ESD workbench/table?
I need to build my own workbench. I have the matting, the 1 MΩ grounding wire is connected directly to a ground running from an electrical cabinet to the ground.
My table is constructed of Textube and ...
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Difference between Surge, ESD and EFT
I was going through this ESD Presentation where I noticed the below image:
I'm trying to understand the different types of overvoltage and they have given the classification above.
In this, what I ...
user220456
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In-house electrical fast transients (EFT) test
I am trying to simulate electrical fast transients (EFT) in order to see if our device is compliant. I am aware that the test that I am conducting is not the most accurate; since we are still in the ...
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ESD Clamping diode specification
I'm using this Ethernet PHY
I've connected the ESD diodes on the Ethernet differential signal lines.
When I use this part the device is failing ESD.
When I use this part the device works fine.
Can ...
user220456