Questions tagged [clearance]
Clearance denotes the shortest distance between two conductive parts as measured through the air.
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How to interpret External Clearance spec on HCPL3700M IC?
The spec for the HCPL3700M (AC voltage detection IC) lists an "External Clearance" of ≥7.4mm.
Is this saying that no component or exposed trace should be within 7.4mm on any side of the chip?...
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Clearance error on pin header solder pads in Eagle
I am getting a clearance error on the Sullins connector PPTC191LFBN-RC. I got the EDA models from Octopart. On including this model in my design I am getting a solder pad clearance error on both the ...
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How can I set a clearance in my polygons? Because there is an error of short circuit between poly of GND or 5V and my vias
I tried to solve these errors using blind and buried vias, but the errors persist. I want when I repour the poly, it creates a clearance between the vias and poly. Or another solutions for the error. ...
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Same net overlapping pads ok?
I'd like to keep the option between components with slightly different footprints. In this particular case it's tactile switches with either 6.5mm or 8mm distance between legs. It looks ok to me but I'...
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How can I disable hole to polygon clearance in Altium?
I have a polygon reaching to the outside of the board. There I want to place mousebites for the panel, but when they are placed, there is a clearance generated around the holes that I don't want:
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When does UL allow a user to access the a metal component connected to AC MAINS through a Y capacitor?
This is a 1kV SMPS design and it is considered a PRIMARY CIRCUIT by UL because it connects directly to 120V AC MAINS. It does not expose its 1kV output directly to the user, but uses the voltage ...
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What are good values for standard design rules (like clearance, trace width, etc.) in PCB design?
I am working on a project for LED control with MCU and LED drivers. I have an input voltage of 24 V and a DCDC converter to 3.3 V for the MCU. Each LED controller will have an output current of 1 A.
I ...
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Typical filled zone clearance
What are typical clearance settings for a filled zone (GND) on a PCB with 3.3V and 12V voltages? Is 0.25mm enough?
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What is a correct method to measure safe maximum voltage of a PCB?
I have a small (24 x 15 mm) PCB for a custom connector. It is intended for low voltage (< 48 VDC) applications, but I am interested in measuring it in order to provide customers a reasonable ...
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Creepage between layers on a PCB
I'm currently designing a power supply with high isolation between primary and secondary sides and have to comply to standard distances on clearance and creepage.
My question is regarding creepage, I ...
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How to measure distance between two pads' solder-mask clearance in Altium
I'm new to Altium and want to measure distance between two pads' solder-mask clearance using Reports-->Measure. I tried activating solder-mask layer only and then tried to measure like regular ...
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Altium designer clearance constaint Between track on toplayer and pad on toplayer
I am a student and i want to design a PCB. I am using Altium Designer 22 and I selected 0.5mm for clearance constaint rule but i got this error. If i select 0.3mm i still got the same error. How can i ...
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EN 61010 Creepage and Clearance questions
My PCB has to meet EN 61010 safety standard and i had a question regarding creepage and clearance values.
Has anyone got any experience applying this standard and when the creepage and clearance ...
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Trace clearance and creepage distance between similar high AC voltage paths
In my project I need to control 2 relays from ESP-12E,
I have isolated AC & DC side in my PCB design by 4mm
PCB Material : FR4, with general Silkscreen coating (green polymer coated)
According to ...
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PCB clearance/creepage with dead metal
I have PCB design where there are two pads the may be shorted (manually in assembly) or left as is, depending on the product model. The through hole circular pad is actually for a terminal block. I ...
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Altium - Hole to hole clearance rule that only applies when nets are not the same
Our PCB manufacturer specifies that there should be a minimum clearance between holes of 0.5mm when nets are different.
I am getting a lot of errors when I have thermal pads with embedded vias closer ...
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Polygon repour clearance rule
I have some trouble editing a project, I had to replace some footprints on a board and thus rebuild polygon planes on top.
As you can see on the first picture, after rebuilding the polygon, the shape ...
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How can I set clearance based on IPC-2221?
Below are two pictures.
The first picture is from IPC-2221. I made the second picture.
Which categories do the L1, L2, L3 and L4 clearances in the second picture belong to in the first picture at 310 ...
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How should the clearance calculation be on a coated PCB?
How many mm should the clearance be between the A and B pads in the picture below?
And clearance between C pad and D pad?
And clearance between E pad and F track?
And clearance between F track and G ...
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Galvanically isolated voltage PCB track clearance requirements
I am designing a PCB to switch high voltage (440VAC) from a microcontroller.
In this project, the 440VAC voltage is galvanically isolated from the microcontroller circuit. I am using an opto-coupler ...
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61010-1 Clearance Distance from PCBA to Enclosure Wall
I am having some difficulty regarding the interpretation of 61010-1:2010 with regards to spacings. I think this is more of high level question/s at this point.
Summary of Problem
Scenario
I am placing ...
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Creepage and Clearance for Connectors
I’m looking to mount SMT pogo pins on a PCB. The connectors will see a maximum working voltage of 120VDC between any two pins, but only when connected to their corresponding female header.
If the ...
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IEC 60664-1 clearance between phase and earth
With IEC 60664-1 you require clearance between phase and earth.
But if you have a resistor voltage divider between phase and earth do you need the same clearance between the pads of the resistors?
Or ...
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6.6kV digital isolator pad clearance
I was wondering about digital isolators. I have some temperature sensors installed inside the windings of a 6.6kV motor. I would like for my system to not be completely destroyed in case of a short.
...
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Altium 21.1.1 - Disable component clearance
I'm royally confused!
I have Altium 20.x.x on one PC. I do a PCB design on this PC and I have no issues. I port that same project to Altium 21.1.1 and suddenly I have major clearance issues when I go ...
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Minimum spacing between PCB components
I am laying out a 2-layer PCB that has only through hole components, and I need it to be as small as possible. I was wondering how small I can set the clearance rule between the components?
When I ...
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Maintaining clearances in HV MOSFET footprints
I'm thinking of making a prototype PCB which would use a bridge rectified AC, which will end up with peaks around 350V in my area (+/- some smoothing). It's a through-hole design and the circuit will ...
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Trace clearance for 500V insulation test
Part of my job is to measure insulation resistance of cables using a tester, such as a Fluke 1587. We measure insulation resistance at 500 VDC. We have to measure insulation resistance pin to pin and ...
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Track clearance with flex region cutout in Altium Designer
In Altium Designer, I created a simple rigid-flex board with the 4 layers in the rigid part (top, in1, in2, bottom) and 2 layers in the flexible part (in1, in2).
I set 5mm clearance on a top layer ...
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Altium Collision DRC error? Cant figure out why
i have finished my PCB design with Altium. I ran the DRC, to check if there are any errors. Strangely i got like hundreds of errors. First i couldn't find out why, but i managed to narrow it down to ...
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Why does increasing altitude (low air pressure) results in lower resistivity/ breakdown voltage?
I got this question because the creepage and clearance distances need to be adjusted for altitude. The higher the altitude, the higher the distances should be. It seems to me however that the contrary ...
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Heatsink Crossing Primary and Secondary Sides in Switched-Mode Power Supply
I've taken apart a non-oem laptop power supply. There is clearance on the board between primary and secondary. However, they've placed a single heatsink across the board for the primary and secondary ...
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Pads very close together, no space for guard ring? What should I do?
Introduction to the problem
I use an op amp to buffer the output of an in amp and to drive the input of an ADC, so the signal path looks basically like this: in amp -> op amp -> ADC
The device ...
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Proper implementation of creepage and clearance on high-voltage PCB
I am designing a 3-phase voltage detector based on optocouplers as shown below:
simulate this circuit – Schematic created using CircuitLab
For this I need to follow DIN 60664-1 and my biggest ...
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Clearance of Exposed Nodes on High Voltage Relay
I'm trying to use this high voltage relay for a machine that will assist in HI-POT tests. The relay can handle about 10kVpeak according to the datasheet and I need it to handle 3.5kVrms maximum. I've ...
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Barrier and slot within reduced area on a PCB
Imagine this situation in a little area of your PCB:
According to the worst case and used material, I need a creepage distance = 30mm. According some tables, clearance must be 30mm. First Red banana ...
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When to use slots instead of barriers in high voltage design?
I have read a lot of information about the clearance and creepage strategies, distances, materials, etc..
I am designing my first HV PCB, main LV circuit will be on TOP and HV (6KV) on the bottom. ...
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crossing 240 V traces on both top and bottom sides of a 2 layer PCB
My situation is the same as the crossings encircled in white from Can I place 220V Live traces on top and bottom of PCB?
Therefore, running Line traces on the top layer and Neutral traces on
the ...
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Altium: how to assign a net class to unconnected pins?
I have PCB with a clearance rule for nets that can be exposed for higher voltages:
In the schematic I put a blanket around the area I need to be assigned as higher voltages nets (I called this class "...
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Clearance distance and resin filler
I'm designing a circuit to detect presence of AC line voltage. It's actually a very simple device with AC side made up of a 200Kohm 1W resistor and an optocoupler and a protection diode.
There will be ...
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Constrain plane clearance from annular ring in Altium
I need to constrain a plane from shorting to the annular rings of a number of vias.
The dialog found at ...
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Isolating main power traces on backside of the PCB
I am currently making a build-in PSU for my own audio-effect-rack-thing.
The internal PSU consists of two print-transformers(THT), one for 6VAC and the second one for 9VAC. These are also pretty low ...
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UL 840 clearances
The table 8.1 in UL840 doesn't consider clearances for voltages less than 50V (for example). I have to use a clearance of 0.2 mm on the PCB for the case of overvoltage category 1 and pollution degree ...
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Maximum allowable voltage between PCB traces
I have some confusion regarding the guidelines for clearance between surface uncoated PCB traces (specifically component pads). IPC-2221 guidelines and other guidelines and standards indicate spacings ...
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High Voltage Capacitor Lead Clearance
I am designing a high voltage board, 10,000 VDC. I wish to use a suitably rated capacitor such as the DHR4E4A102K2BB. When I have been studying the ...
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Electrical isolation problems when routing between pads of SMT resistors/caps
According to answers to this previous question, routing traces between the pads of SMD caps/resistors, as shown in the picture, is not dangerous as long as trace to pad clearances are obeyed and the ...
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Creepage distance over pcb
How to measure creepage distance over pcb ?
Is creepage and clearance distance measure by pbc layout or soldering?
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Insulation of SiC Diode
I am reading about creepage distance and clearance and came across a T0-247-3 SiC diode (IDW20G120C5B). This diode is rated for 1.2kV which would mean that it won't break down at let's say 800V, which ...
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Cleaning up GND/PWR-plane air wire errors in EAGLE + bonus questions
So I've just finished up my first complete PCB board. The layout is 4-layer based, set up as ((1*2)*(15*16)) ---not sure if it should be ((1+2)*(15+16)) or ((1*2)+(15*16)) instead, please advise--- ...
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KiCAD Component Pad Clearances
I'm using KiCAD version 5, and I have an issue with it. Previously, I've been using OrCAD up until the point to where I needed multiple layers for my board. So, I redesigned my components, but I'm ...
