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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What should be distance (gap) between Pack+ input and GND?
There is a BQ4050 battery management IC and its reference design schematic. In the below image, there is a spark gap symbol I think labeled as E2, E3, and E4 between battery inputs and GND. I want to ...
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ESD protection device selection
I want to select a ESD protection IC for my circuit with the following conditions:
Battery based and ultra-low-power
Battery voltage 3.6 V
My sensitive chips inside my circuit has Absolute Maximum ...
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Metal chassis grounding with wall wart supply, ESD test failed
We're building a device which takes its input power from a 12VDC wall wart PSU, and has a metal chassis. We just passed preliminary EMC/EMI test, but in the ESD test an 8kV jolt to the chassis killed ...
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ESD on two different materials
I am conducting ESD testing on two types of materials with a setup that closely follows the 61000-4-2 standard. We have incorporated both isolation material and a ground plane into our setup.
When I ...
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Is the blue Weller WECP-20 ESD safe? [closed]
There are two Weller WECP-20 soldering stations. One blue and one black.
The black one has a label "ESD SAFE" and the blue have no ESD label at all. But is the blue Weller WECP-20 still ESD ...
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SPI device stops working when integrating Schmitt triggers and ESD diodes
I am integrating a BME680 temperature, pressure and humidity sensor using SPI.
When I only use 33 Ohms series resistors, the system works fine. However, when adding Schmitt triggers (NL27WZ17DFT2G), ...
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ESD knocking out PHY on device with unisolated POE
I inherited this design, one problem I am having is ESD on the chassis knocks out the PHY, sometimes it can't even be reset via software. I am curious if anyone can spot any glaring errors with the ...
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Questions regarding TVS-diodes and grounding
I am currently working with solutions to pass the ESD-requirements for EMC. I have used TVS (ESD)-diodes in the past to good result, but never really understood exactly why they work. Sadly, this is ...
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Can I mitigate risk ESD to a sensitive device with small insulating panels?
I have an electrostatic-sensitive device held in an aluminum block. It has to be aluminum for temperature control. I recently destroyed said device by touching the aluminum block on a low-humidity day....
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Optocoupled Input (3..24V) overcurrent/ESD Protection
I'm designing relatively wide voltage range (3..24V) isolated input for reading the push-pull output state. Input source is going to be from a water counter, some 3-phase motor controllers, water ...
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Medical device on patient's bed..Cannot earth the Chassis..How to provide ESD protection?
We are developing a medical device, which will sit on patient's bed. So, the medical device chassis can't be connected to earth. The powersupply of the device is isolated (2MOPP and 2 MOOP), medical ...
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Need USB C cable / connector insulation voltage....and ESD on shield, will impact the internal signals
Any one know how much voltage the standard USB C cable insulation can withstand?..Also want to know shield to internal conductor insulation..If I apply ESD on the connector shield, will it impact the ...
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Tie all unused GPIO to GND?
Recently, during a discussion with a senior electronics engineer on an industrial project that operates at 48V and is housed within a metallic casing, a point of contention arose regarding ESD ...
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TVS Diode current flow at breakdown
This was a question asked to us by our client.The question is
'We have a TVS diode with a break down voltage of 31V.When a pulse of amplitude 31.7V and a duration of 100ms second is applied the diode ...
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Grounding ESD Table
I work in a manufacturing plant and we are setting up new ESD benches. Essentially, the table is grounded to the ceiling of the building and then multiple work benches are connected to that bench with ...
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Balancing high voltage and ESD safety for a work bench [closed]
I own various large stainless steel benches which I'm using to sit heavy equipment (200kg+ per bench). Some of this equipment will need new electronic components i'll have to wire up, such as 120vac ...
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Can air itself be theoretically considered as a (very poor) wireless ESD grounding strap?
There are many kinds of questionable ESD wriststraps available which
claim to provide ESD protection "wirelessly". When asked about how
exactly they work, they cite dubious claims about ...
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ESD Workstations in Manufacturing Facility
I am a manufacturing engineer for a company that just inherited a large electrical build. I am struggling to find ESD information for multiple workbenches. This is my last resort so I am hoping you ...
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Is external ESD protection needed with the MAX3051?
I'm currently doing my first Project using custom PCBs.
It's a CAN based system to control things around my house (lights, blinds, sound, etc.).
I'm planning to use multiple STM32F103C6 (in Form of a ...
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How to select ESD TVS diode? [closed]
This is the following specification of my circuit
Vin 8V to 32V
The breakdown voltage should be 33V of TVS
I don't know what clamping voltage means please simplify it for me
What should be Vc?
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MCU Input ESD Protection + debounce
I'm working on a device which requires reading from a reed switch (slow, water meter) which should work in a bit noisy environment (a few relays switching back/forth on the same board, triacs and ...
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Plugging in USB causes MCU to die
I have seen the below circuit at work. It has two supporting circuits on one PCB, each with its own ground.
The circuit with the micro-USB is tied to the MCU circuitry via L3, L4, and C30.
The MCU ...
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Power line configuration [closed]
For power, which configuration is best?
Fuse first, followed by an ESD diode
ESD diode first, and the fuse next
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How can I protect MCU SWD portf from ESD?
I have connected two TVS diodes close to header, and Resistor for limiting the current.
Is it enough to protect the ports from ESD or i need to add anything else or correct this schematics?
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Using a Plug-In AC/DC adapter Output's Negative as Earth GND
Now, this is not a general question about any plug-in 12V DC supply with a barrel connector output. They are all different. There are those without Eath GND wire in the AC power input, those with it, ...
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Why do they ship a metal sheet with the breadboard?
My breadboard came with a metal sheet:
The breadboard should hardly be ESD sensitive. And if it would be, then there's still the double sided tape separating the breadboard from the metal sheet. From ...
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Spikes appearing on the UART pins of Microcontroller when connecting to supply
I am using STM32G0c8t6 microcontroller to make a BLDC motor controller. I am connecting the Rx and Tx of UART to a VCU and they are sharing the same battery. Apart from these, there is no other ...
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How can I utilize PSpice for ESD simulation?
Issue: I do not know how to build a ESD simulation model in PSpice Orcad capture.
Question: What is wrong with the simulation circuit? The simulation result seems like the ESD is not discharging ...
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Arduino Uno ESD ruggedness
I want to route one of the Arduino's digital output pins out of a device, to interface with other instruments via a several meter long coax cable. Typically, I would implement measures against ESD for ...
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Is a 100 Ω/1 nF RC low-pass filter enough to protect a microcontroller I/O pin from ESD?
While researching ESD protection on this site, I came across this question.
The answer by Peter Smith contains a comment by @Ale..chenski:
Just a nit pick: if you can afford 100R and 1nF to ground on ...
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ESD protection when reverse stand-off voltage and required clamping voltage are close together
The circuit under consideration is to be powered by four 18650 li-ion cells in series. These cells are in a holder and user replaceable so there is risk of the contacts being touched and adding esd ...
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Can "fried" semiconductor devices recover themselves over time?
When this whole "smart soldering iron" craze was just getting started, I jumped on the bandwagon and got myself the very first revision TS100. What I also got then is the complete inability ...
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Ferrite bead value for a LIN bus protection circuit
What is the proper value for FB1 in relation to the surrounding capacitors in this diagram?
The FB1 resistance is measured to 0.76ohm and package size is 0603. All components are AEC-Q200 rated.
The ...
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PCB Design guidelines for "hot swapping"
I am designing a PCB with JST EH connectors, which are connected to a multi pin socket exposed to the user. The multi pin socket provides +24V, CAN H, CAN L and GND. I have experienced that the PCB ...
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Auxiliary mechanical anti-ESD measures
If a PCBA within a plastic enclosure is prone to malfunctioning due to ESD air discharge in proximity of enclosure seams and openings, but changing the hardware or plastic design is not an option, ...
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ESD protection: connect wrist strap to ESD mat or directly to grounding point
For our workshop, I'm thinking about buying a big ESD mat to cover the whole workbench (5.5 m), so it won't be a "ready to use" one, but a roll to cut to the right dimensions, and to which I ...
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What (semi-) permanent infrastructure be added to ESD harden an already-constructed space?
I have a newly-constructed university center which I would like to harden to ESD. Unfortunately, I became involved in the process too late to ensure that proper antistatic flooring was installed. At ...
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How can you protect exposed ground pins from ESD?
If I have a DC powered PCB that is floating (not tied to earth ground), and a human touches the ground plane causing an ESD event to occur, what can be done in terms of design to prevent damage to the ...
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Absolute Maximum ratings of a device
In most of the devices I have seen so far, the absolute maximum ratings of the pins of the IC are given with respect to voltage.
For example, the maximum voltage applicable on a pin would be something ...
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Plastic enclosure, ESD considerations
I am working on a product with three plastic components: an injection molded enclosure (Lexan, polycarbonate), a 3D printed mounting tray (ESD PETG, carbon nanotubes) onto which my PCB is mounted, and ...
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Can someone explain USB ESD-protection on Nucleo 144?
On the STM32 Nucleo-144 eval board, there are 3 different ESD protection devices for the USB port:
U19 = USBLC6-2SC6
U21 = ESDA7P60-1U1M
U22 = ESDALC6V1-1U2
Source:
https://www.st.com/en/evaluation-...
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Does ESD protection cause voltage leakage?
I have a this schematic for powering ESP32 over the usb and communicate PC with usb interface. It works perfect. But there is a interesting error. while I am powering ESP32 with Lipo battery (In case ...
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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 ...