All Questions
Tagged with esd pcb-design
19
questions
1
vote
1
answer
151
views
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 ...
- 79
0
votes
0
answers
49
views
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 ...
- 135
10
votes
4
answers
1k
views
System level improvements for a product in a plastic enclosure without exposed connectors to pass IEC 61000-4-2. Discharges through slit zapped LEDs
Our product failed ESD during precompliance.
Specifically, 4 LEDs got zapped, six times each (3 positive and 3 negative charges), during an 8kV air-discharge test, causing permanent damage to the LEDs ...
- 754
1
vote
1
answer
281
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Is it OK to route under small mosfet transistor?
I have a 2-layer board where I am thinking of routing TX and RX to microcontroller under a small P-channel mosfet.
I know some parts can be considered sensitive and one should not route under them.
Is ...
- 31
0
votes
1
answer
253
views
Contact ESD protection vs Air gap ESD protection
There many ESD diodes available in market for ESD protection from connectors or 'touch surfaces' of product.
But how about air gap ESD attack? What if I have large PCB with connectors at the end, ESD ...
- 393
1
vote
2
answers
1k
views
When ESD protection is necessary and where should TVS be placed?
I'm designing a PCB in which the main ICs are a STM32F0 microcontroller and an INA226. These IC have some IO pins exposed in a header and the device will be handled by people.
Is it likely that an ...
- 37
1
vote
0
answers
329
views
Voltage spikes caused by stray wire
I recently had a PCB designed which has several analog, digital, and power elements. The board is powered by 24Vdc which is stepped down using an LDO to 3.3V and 5V. These voltages are used to power ...
- 11
0
votes
2
answers
538
views
How to connect the GND with the metal case of the robot
I have a PCB design inside a metal case of the robot. The robot is mobile, it moves on wheels.
The problem is how to connect the GND with the metal case of the robot. Direct connection is not safe, ...
0
votes
1
answer
731
views
Connection of LAN8742A nRST pin causes failure when ESD strike
My circuit uses LAN8742A ethernet phy. The system has a metal case and gets 220V AC to power supply board. After converting 5V DC it goes to my board that has Ethernet and mcu. I screwed case and ...
1
vote
1
answer
2k
views
ESD strike breaks the LAN8742A ethernet phy
My circuit uses LAN8742A ethernet phy. The system has a metal case and gets 220V AC to power supply board. After converting 5V DC it goes to my board that has Ethernet and mcu. I screwed case and ...
2
votes
1
answer
285
views
ESD potection in the PCB
I am using micro USB socket to charge the battery in one of the device and now we are planning to go for CE certification for which we are doing EMI/EMC test. For the ESD IEC 61000-4-2 (+/- 6 kV ...
- 403
1
vote
0
answers
195
views
ESD (and EMI) protect long slow lines
I'm designing a measurement and control board to interface with an old (70s) PLC. The board consists mainly of I/O ports, both analog and digital in- and outputs. To have my boards not fried by the ...
- 113
5
votes
1
answer
4k
views
ESD/surge protection with TVS and spark gap
I made a footprint for a TVS diode with a spark gap underneath it. The standoff height of the diode is about 0.2mm.
A few questions:
Is there any benefit of putting a spark gap and a TVS in parallel?...
- 347
2
votes
2
answers
510
views
Failing LiPo charger circuit
Working with microchip MCP73831T chip to charge a single LiPo cell. We are producing by the 1000 unit and getting significant failure of the charger IC. I suspect we need ESD protection on the 5V ...
1
vote
1
answer
2k
views
Is ESD protection necessary on a battery powered device?
I'm currently working on a PCB design that will be battery powered. However, it will be necessary at times to plug the device into a computer to program it.
When the PCB is plugged into the computer,...
- 2,036