hybridfree/eevblog-posts huggingface dataset:
unpopulated footprints on PCB? - Page 1
Forum section: electronics / general

author: oliver602
author_rank: Regular Contributor
timestamp: November 23, 2011, 07:38:27 am
content: Often see PCB's with unpopulated footprints so the same PCB can be used for variations of the same product or perhaps even different products. Is there a a common way to do this in PCB design software? For exampe, I'd like to make a PCB with footprints for either a coin cell holder or AAA battery holder and be able to change resistor values for LED's.

author: hacklordsniper
author_rank: Frequent Contributor
timestamp: November 23, 2011, 07:42:29 am
content: Quote from: oliver602 on November 23, 2011, 07:38:27 amOften manufacturers make single pcb for more models to save costs and/or remove components from exsisting design later in production to save costs. Additional components could also be used only in testing/prototyping stage and are not needed in final producsts.

author: armandas
author_rank: Frequent Contributor
timestamp: November 23, 2011, 08:13:42 am
content: Quote from: oliver602 on November 23, 2011, 07:38:27 amIt depends on what software you are using. Altium has variants, for example, but if your software does not have such feature, you can do this yourself by having multiple BOMs.

author: Neilm
author_rank: Super Contributor
timestamp: November 23, 2011, 07:01:06 pm
content: The other reason manufacturers might have empty footprints would be for "just in case" scenarios. These would generally be for EMC scenarios where having footprints on the board in the area you might need something would save the expense of re-laying out the PCB if later testing revealed that they were needed.Sods law being what it is, I have yet to find one in exactly the right place (or correct footprint type)Neil

author: oliver602
author_rank: Regular Contributor
timestamp: November 24, 2011, 09:22:43 pm
content: Thanks for the replies. I'm using KiCad and after a quick inspection I can't find anything that would allow for variants. Anybody have tips on how to achieve something like this in KiCad?

author: ElektroQuark
author_rank: Unknown
timestamp: November 25, 2011, 09:12:46 am
content: Try the KiCad user mailing list at Yahoo:http://tech.groups.yahoo.com/group/kicad-users/There are very experienced KiCad users there.

author: Jon Chandler
author_rank: Frequent Contributor
timestamp: November 25, 2011, 03:23:41 pm
content: There's no reason not to just include the extra footprints on the board with a note in the BOM about using one location or another, or to use different parts values in different situations.If you'd like, include the different parts on the schematic (2 batteries for example) with a note to use one or the other.

author: Greg J
author_rank: Regular Contributor
timestamp: January 08, 2012, 04:03:44 pm
content: Good stuff armbands , +1 (not the google shite one).
Circuit film/sheet? - Page 1
Forum section: electronics / general

author: king.oslo
author_rank: Frequent Contributor
timestamp: December 09, 2011, 02:17:55 pm
content: Hello there,I was asked about the possibility of making a flexible PCB, like a sheet of plastic or fabric, with surface mount LEDs. Ideally, one which is so flexible that it can be rolled or folded to take up less space while not used. The guy who asked me wants to either make massive LED-array-sheet with thousands of LEDs, or smaller units which can be connected to make up one massive array. We are talking several meters in length and width. I reckon the placing and soldering will me a momentous task, probably not to be attempted by a hobbyist. So I said I cannot do it.However, I offered to ask on this forum if somebody is aware of processes which can do this? Are there companies which makes something like plastic sheet pcbs, that can be assembled robotically?What are your thoughts?Thanks.M

author: ciccio
author_rank: Frequent Contributor
timestamp: December 09, 2011, 03:37:12 pm
content: Flexible PCB are standard products from a lot of manufacturers.The following is an example from an Italian one:http://www.somacis.com/prodotti/prodotti.php?cat=4&catname=&subcat=&language=enRegards

author: mosrob
author_rank: Newbie
timestamp: December 09, 2011, 08:43:09 pm
content: Here's another one that makes "Flexible circuit boards":Poly IC, Germany:http://www.polyic.com/

author: IanB
author_rank: Super Contributor
timestamp: December 09, 2011, 09:29:04 pm
content: At the sizes you are asking about, it might be better to use some kind of fabric and wire up the LEDs with conductive thread. People have done that a lot with clothing.

author: ejeffrey
author_rank: Super Contributor
timestamp: December 16, 2011, 08:17:09 pm
content: I am not sure whether conventional flexible PCB manufacturing typically can handle such large sizes, but I doubt it.It is possible to do screen printing or industrial inkjet printing of conductive inks onto rolls of plastic. You should actually be able to order this in quantities that are large for a hobbyist or one-off, but not off the charts. I don't know how you would do the placement: it is certainly possible to do machine placement on a rolling web, but I don't know what standard process might accommodate that -- if you can't find someone who can already do it tooling would obviously be extremely expensive. If you could solve that, you could then laminate the whole thing with another layer of plastic and be off and running.
Eagle V6 beta? - Page 1
Forum section: electronics / general

author: IanJ
author_rank: Unknown
timestamp: November 04, 2011, 09:39:19 pm
content: Hi all,Downloaded and installed, but not had much time to play.http://www.cadsoftusa.com/betatest/It says ver win-5.91.1-beta but I notice it's saving the files in XML.........so is this a public release of V6 with all it's bells n whistles.....?Ian.

author: Unknown
author_rank: Unknown
timestamp: November 04, 2011, 09:58:00 pm
content: I would think so based on the message than v5 license holders may have to upgrade their license to v6. See alsohttps://www.eevblog.com/forum/index.php?topic=5437.0.

author: tinhead
author_rank: Super Contributor
timestamp: November 04, 2011, 11:44:21 pm
content: not necessarily public beta v6 but first step in that direction.However UPDATE_en.txt the says:EAGLEVersion 5Update Information==================================This file contains information for users of previous EAGLE versions.Please read this file entirely if you are updating from an EAGLE versionprior to 5.91.1!WARNING: The data structure in this version is completely different fromthat in older versions! Once you edit a file withversion 6.xyouwill no longer be able to edit it with versions prior to 6.0!PLEASE MAKE BACKUP COPIES OF YOUR CURRENT BOARD-, SCHEMATIC- ANDLIBRARY-FILES BEFORE EDITING THEM WITH VERSION 6.0!and indeed the file format is xml.

author: IanJ
author_rank: Unknown
timestamp: December 14, 2011, 07:40:13 pm
content: Hi all,V6 is now available.Ian.
Offseting header footprints - Page 1
Forum section: electronics / general

author: slateraptor
author_rank: Frequent Contributor
timestamp: November 22, 2011, 09:18:24 am
content: https://www.eevblog.com/forum/index.php?topic=5650.0Second comment by joelby links to a Digilent CPLD breakout. The offset JTAG header holes immediately caught my attention.First Google search resulted in:http://www.sparkfun.com/tutorials/114Based on Sparkfun's board house tolerances, 5 mil alternating shimmy results in a self-retaining fit. Not too sure how I feel about the author's solution. Admittedly, it's simple yet clever.Just thought I'd share.

author: ejeffrey
author_rank: Super Contributor
timestamp: November 22, 2011, 10:34:49 am
content: The first place I ran into this solution was sparkfun's eagle library. I wouldn't use it for a prototype board: there are plenty of ways to get the headers aligned good enough, especially if you don't care about cosmetics. Without experimentation on a particular PCB house and design rules, I wouldn't count on the manufacturing tolerances being sufficiently predictable to get the offset right. I would hate for a prototype board to be ruined because the drills were rounded from imperial to metric sizes.For production where you are making lots of identical boards always manufactured by the same board house, this sounds like a great idea.

author: slateraptor
author_rank: Frequent Contributor
timestamp: November 22, 2011, 11:05:54 am
content: Quote from: ejeffrey on November 22, 2011, 10:34:49 amAgreed, hence the "based on Sparkfun's board house tolerances" and "not sure how I feel about the author's solution" comments.Soldering with the PCB laid upside down on perf board held by a panavise works well for vertical headers. For right-angle headers, a pair of mechanical fingers works well since they're mounted towards the edge of the board.

author: joelby
author_rank: Frequent Contributor
timestamp: November 23, 2011, 02:16:29 am
content: It also seems like an nice solution where you don't necessarily want to permanently solder the header onto the board. I do this with my PICkit programmer - just put a 1x6 header into the end. The staggered pins would make it less susceptible to just falling out.
SchemeIT - Page 1
Forum section: electronics / general

author: l4rtt-1
author_rank: Contributor
timestamp: January 11, 2012, 09:23:22 am
content: Digikey has released nice little tool for drawing quick schematics:http://www.digikey.com/schemeit?wt.mc_id=PressReleaseIt's browser based and you can also search parts from Digikey with it.Here's a tutorial for it:

author: Rerouter
author_rank: Super Contributor
timestamp: January 11, 2012, 09:37:57 am
content: wish they would tie in some spice capability, such a lacking tool with so many schematic editors,
OrCAD 16.0 - Page 1
Forum section: electronics / general

author: Slobodan
author_rank: Regular Contributor
timestamp: November 11, 2011, 04:27:45 pm
content: If anyone know where i could find additionalfootprint librariesfor OrCAD 16.0, please post a link.

author: johnmx
author_rank: Frequent Contributor
timestamp: November 11, 2011, 07:47:29 pm
content: Interesting question. Not sure if that exists. I always design my own footprints.

author: Armin_Balija
author_rank: Regular Contributor
timestamp: November 12, 2011, 05:45:23 am
content: I've been more frustrated with their SPICE analysis software because I don't know where to get a hold of their SPICE footprints. Going from MultiSim to OrCad has been interesting and I know OrCad has the potential to blow MultiSim out of the water on all fronts but the UI on MultiSim is just so user friendly that it's ridiculous. Does anyone have any links to some SPICE libraries for OrCad while we're on the subject of OrCad libraries?

author: Slobodan
author_rank: Regular Contributor
timestamp: November 12, 2011, 01:44:16 pm
content: I tried to make my own footprints, but i just don't known how. If i can't find them online, i will have to learn how to make them...
Hole/Pad size - First PCB ever  - Page 1
Forum section: electronics / general

author: toli
author_rank: Frequent Contributor
timestamp: September 26, 2011, 01:30:49 pm
content: Hi Guys,I've finally come around to designing my first PCB for a discrete linear regulator I've designed. I have some experience in IC layout (Cadence Virtuoso) but non when it comes to PCB's. I've decided to use FreePCB as its seems very easy to use, and I a coworker recommended it. At the moment I would like to try and stick to that program.Now to the question:I've got a few large capacitors I'm using, which have up to 1mm diameter of the leads. So I understand its about 40mil (39.37), right? In that case what size of hole and pad I should use? Will 45/90mil be good? I was quite surprised to see that the RAD-709 footprint (capacitor with 7.5mm LS, and 18mm dia.) available in FreePCB has 28mil/65mil hole/pad size for these large capacitors, and I can't understand how its supposed to fit them.I'm sure I'll have some more questions once I move along, but that is all at the moment.Thank you.

author: Time
author_rank: Frequent Contributor
timestamp: September 26, 2011, 04:10:29 pm
content: Is this going to be printed? milled on copper clad board? Are you going to be soldering by hand? Does the capacitor casing cover the pad on the top so you only have solder access from the bottom?Really things like this come with trial and error. If you are soldering by hand your best bet is to make things bigger if your design does not depend on such factors.I suggest figuring out how to print your board to scale (1:1) and examining the layers to really get a feel for what its going to be like once made. By print I mean on paper with ink, not PCB type printing

author: toli
author_rank: Frequent Contributor
timestamp: September 26, 2011, 04:12:21 pm
content: I'm going to have the boards made, and solder it by hand.

author: IanB
author_rank: Super Contributor
timestamp: September 26, 2011, 10:09:23 pm
content: What Time said seems like really good advice. Print your design on paper, glue it to some thin card, use a pin to make holes where the component leads go, and lay out your components to see how they fit. You will be able to check things like clearance between components, correctness of lead spacing and possible improvements to the layout.

author: toli
author_rank: Frequent Contributor
timestamp: October 04, 2011, 07:42:14 am
content: Well my first PCB design is doneI've asked a couple of my co-workers who have quite a bit of experience in this to have a look and they gave me the ok to send it to manufacturing.I've noticed iteadstudio (which I plan on using) are asking for .txt drill file, and .GBL/.GTL/etc for the layers files. I have .GRB for all layers (RS-274x format as requested) and .drl for the drill file. I can easily rename them, but I was wondering if anyone has sent these file types to iteadstudio and knows if its fine. I've sent them an email by got no response for a couple of days now.
Removing all solder mask from a board? - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: October 02, 2011, 11:52:24 am
content: Does anyone know of a way (chemical?) to remove all solder mask from a PCB, leaving the copper/gold behind?Dave.

author: EEVblog
author_rank: Unknown
timestamp: October 02, 2011, 11:54:11 am
content: Well, wadda-you-know:http://www.rbpchemical.com/chem_doc/SolderMaskRemover.pdfDave.

author: ablacon64
author_rank: Frequent Contributor
timestamp: October 02, 2011, 02:46:50 pm
content: I wonder why would you want to do that?Edit:Have you seen those?http://www.circuitmedic.com/features/514.shtmlhttp://www.alibaba.com/product-free/214941207/Cured_solder_mask_stripper_remover.html
VeeCAD Stripboard Editor - Page 1
Forum section: electronics / general

author: ChrisKiwi
author_rank: Contributor
timestamp: September 16, 2011, 05:39:44 am
content: Hi AllI haven't seen any mention of this so though it worth while posting about ithttp://veecad.com/is a "Veroboard" layout editor that accepts net list's in various formats and allows layout using a Net List. I've found it very useful and so purchased a license to have a few extra features and support the developer. The freeware version is still quite useful though.
I feel like I stumbled upon a gold mine! - Page 1
Forum section: electronics / general

author: Armin_Balija
author_rank: Regular Contributor
timestamp: August 24, 2011, 11:04:25 pm
content: I've been wanting to create and design my own PCB's for a while now but don't have any knowledge, experience, or anything like that. We haven't worked with PCB design at the Univ yet because it's still a ways away (still learning theory and all).Anyway, I wanted to learn about it ahead of time and really understand the concepts, principles, and ideas behind good routing and design practices for PCB's. I've read in the past that Dave thinks auto-routing is rubbish. I searched on google for a PCB design tutorial and lo and behold, our very own David L. Jones made a PCB design tutorial. I was oblivious to it and I haven't heard of him talk about it before. I've read a little bit so far, grazed it's pages, and I've got to say it's so neat and organized. I love the straight-forward style and helpfulness and tables and charts of everything in the PDF.Thank you so much Dave for helping me and not even knowing it!http://www.alternatezone.com/electronics/files/PCBDesignTutorialRevA.pdf

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: August 25, 2011, 12:08:33 am
content: I do not know were you stumbled upon.But its good idea to avoid teaser titles.

author: Armin_Balija
author_rank: Regular Contributor
timestamp: August 25, 2011, 12:47:12 am
content: Quote from: Kiriakos-GR on August 25, 2011, 12:08:33 amI'm sorry! Although I assume most people have this knowledge or have seen this before I just felt like it was such a great discovery to me. I will avoid teaser titles from now on!

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: August 25, 2011, 01:28:10 am
content: Ok, when you will find the gold mine, call me to assist.

author: EEVblog
author_rank: Unknown
timestamp: August 25, 2011, 05:00:13 am
content: You're welcome.That was hastily written as a 3 part article for Silicon Chip mag, but once I made the PDF available it's been massively popular.It's been downloaded several million times (no exaggeration), but I stopped looking at the stats a few years back.Dave.

author: patb
author_rank: Regular Contributor
timestamp: August 25, 2011, 07:59:36 am
content: Great article. Thanks for sharing. I didnt know it.Patryk.

author: Unknown
author_rank: Unknown
timestamp: August 25, 2011, 12:29:22 pm
content: Dave you should think of wikifying it, so it can be expanded with time.

author: bullet308
author_rank: Frequent Contributor
timestamp: September 15, 2011, 01:44:42 pm
content: Your "hastily written stuff is far more useful than most anything else out there.Not gold, but golden, to be sure! :-)
PTH Drill sizes - Page 1
Forum section: electronics / general

author: Freighternut
author_rank: Regular Contributor
timestamp: September 18, 2011, 08:17:53 am
content: Is there a rule of thumb for calculating drill sizes for PTH given a component lead size?Also I am a bit confused as to wether the drill NC file should show finished hole size or pre-plate size, does this vary between PCB manufacturers?

author: ejeffrey
author_rank: Super Contributor
timestamp: September 18, 2011, 09:32:48 am
content: Finished hole sizes is the standard at every manufacturer I have used, I assume it is nearly universal. The should specify what they want in their artwork guidelines, along with their standard drill sizes.Check your data sheets, they usually have a preferred footprint with hole sizes. Just round that up to the nearest standard drill size of your board house.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 18, 2011, 09:38:41 am
content: General rule 0.8mm for leaded parts and ICs, 1.0mm for 0.1" pin-headers etc.You want at least 0.3mm above the lead size for easy insertion, but it isn't too critical and going bigger is rarely a problem unless tight alignment is important.As well as lead dia itself, size of part, number of pins and likelihood of bent pins are other considerations - inserting a multi-pin part into close-fitting holes can be near impossible if there are misaligned pins - oversized holes make things a lot easier.Minimizing the number of different sizes is also good as this can sometimes influence cost.You spec the finished size - PCB maker will adjust for their plating thickness.

author: Freighternut
author_rank: Regular Contributor
timestamp: September 21, 2011, 01:40:08 am
content: Thanks Mike and ejeffrey, most helpful as usual.

author: KashmirGR
author_rank: Newbie
timestamp: September 21, 2011, 07:37:31 am
content: There are recommended hole sizes for PTH components based on IPC rules. IPC has rulesvfor three classes of hole size (least, nominal and most). There are also formulas to calculate hole diameter. Here is a lead to one page that discusses calculations:http://en.wikibooks.org/wiki/Practical_Electronics/PCB_LayoutYour pcb vendor may have preferred sizes as well. If you look at pcbexpress.com for example, they have set sizes for through holes (you can find the table on their site).Mentor Graphics offers a footprint viewer for free that has many footprints, which I believe has both SMT and PTH components. Search for IPC land viewer.
Does anyone know anything about PCB timing or Fabrication? - Page 1
Forum section: electronics / general

author: Joy at MCS
author_rank: Regular Contributor
timestamp: August 12, 2011, 06:09:06 pm
content: HiI've got a customer of mine who's asked the following question. This isn't our field so I'd be grateful if anyone could offer any suggestions or info."we need to define the timing characteristics of the existing cards, so that we have a baseline against which the remanufactured card can be compared. The term PCB Characterisation or PCB Timing Characterisation have been used. I am interested in how this is achieved and if you have any useful articles relating to this topic. "Does anyone have any articles or suggestions?Thank you for your help.Have a good day :-)Joy

author: Zero999
author_rank: Super Contributor
timestamp: August 12, 2011, 07:18:11 pm
content: It seems far too vague. Are they asking about fabrication time-scales or the propagation delay of a signal from one part of the board to another?

author: djsb
author_rank: Super Contributor
timestamp: August 13, 2011, 09:21:20 am
content: This might be usefull?http://www.home.agilent.com/upload/cmc_upload/All/GTL91.pdfMost of the other stuff relates to how to design boards not measure the properties of an existing board.David.

author: Rufus
author_rank: Super Contributor
timestamp: August 13, 2011, 12:19:49 pm
content: Quote from: Joy at MCS on August 12, 2011, 06:09:06 pmToo vague to know if it is anyone's field.You need to ask if they are really talking about PCBs (bare PCBs) or about circuits which happen to be built on PCBs.For bare PCBs look at the VNA link posted above and maybe controlled impedance testing athttp://www.polarinstruments.com/.For circuits a scope is the most generally useful instrument to measure timings.

author: qno
author_rank: Frequent Contributor
timestamp: August 14, 2011, 09:32:18 am
content: Get a copy of Dr. Howard Johnson's book of black magic.http://www.sigcon.com/books/bookHSDD.htm

author: Joy at MCS
author_rank: Regular Contributor
timestamp: August 15, 2011, 09:31:27 am
content: thank you. I'll see if I can get a bit more clarification from him ...

author: Simon
author_rank: Unknown
timestamp: August 24, 2011, 11:56:23 am
content: Quote from: Joy at MCS on August 15, 2011, 09:31:27 amTell him to post directly on herewe don't bite

author: Joy at MCS
author_rank: Regular Contributor
timestamp: August 25, 2011, 09:46:59 am
content: I sent him the link with the post of all your answers and asked if he could provide more info or told him to make a profile and post directly.Thank you everyone for all your help. Really appreciatedHave a great upcoming weekend!Joy
PCB design ideas for "Pinstrapping", "Bootstrapping", ETCstrapping via hardware - Page 1
Forum section: electronics / general

author: nuvintage
author_rank: Newbie
timestamp: July 21, 2011, 02:40:47 pm
content: Hello everyone,I'm currently designing a board in which multiple IC's need to configured by strapping (the practice of tying pins high or low based on configuration requirements). I'm trying to opt out of buying expensive DIP switches, and was wondering what other people's elegant solutions to the problem were. I want to be able to have the choice of changing the configuration in the future, so both high/low options need to be available on the PCB. Current ideas include just placing 3 pads in banks while using the pull-up/down resistors as jumpers.Thanks!

author: ejeffrey
author_rank: Super Contributor
timestamp: July 21, 2011, 02:57:58 pm
content: Pull-up resistors plus jumpers to short to ground is the easiest way to go. Better to include a pull up or down resistor than to leave it floating if no jumper is installed.If you don't need to reconfigure a given board, you can just solder bridge the jumper pads rather than installing the jumper pins. You would do this not to save installing the jumper, but if you didn't one someone (i.e., future you) to accidentally change the jumper settings.
P-CAD 2001 to kicad, geda or eagle - Page 1
Forum section: electronics / general

author: myval
author_rank: Contributor
timestamp: June 28, 2011, 09:21:49 am
content: Hi,can anyone convert P-CAD 2001 pcb design in to something I can open and edit/ export to gerber, kicad, geda or eagle is preferred.thank youJosef
Electrical CAD - Page 1
Forum section: electronics / general

author: st1
author_rank: Contributor
timestamp: July 12, 2011, 11:56:38 am
content: Hi guys! I really don't know who to ask about this so I was hopping you guys might have some insights!Where I'm studying "Rafeindavirkjun" (in Iceland) (witch is like a low power electrician)We're using a CAD package called PCSCHEMATIC to create Layouts of houses (Wiring diagrams) Coax antenna plans for homes etc.But I was wondering if there where any other packages to this type of work in ?
KICAD prevents tracks  from being layed where they violate clearance? - Page 1
Forum section: electronics / general

author: makebit
author_rank: Unknown
timestamp: September 29, 2025, 01:25:31 pm
content: Hi,Just to confirm, is it really true that KICAD allows your tracking to go less than 0.15mm apart, even if you set that as a design rule?I know Altium is very good like this, and literally stops you from being able to put a track less than 0.15mm from another track, as long as you set "0.15mm" in the design rules.

author: artag
author_rank: Super Contributor
timestamp: September 29, 2025, 01:42:05 pm
content: It does stop you whilst routing. Can e annoying if you're repositioning something and need it temporarily colliding while you move other items. You can switch it off so maybe that's what's happening if you find it's allowing collisions.

author: Geoff-AU
author_rank: Frequent Contributor
timestamp: October 01, 2025, 11:43:29 pm
content: This was bugging me yesterday and I found the setting, Interactive Router -> "Walk around" or "Highlight collisions". The former prevents you from making DRC problems, the latter just shows you what will be wrong if you proceed.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: October 02, 2025, 12:33:50 am
content: Normally KiCad's interactive router is in shove mode, and it creates room to keep all clearances while routing (even from custom rules I think).But when you put the router in "walkaround mode" does have an extra checkbox to explicity allow DRC violations.There are also some other situations that can create DRC clearance violatons, for example when moving a block, or when increasing the track width of already existing tracks. In those cases you can overrule DRC by holding the>key and thus force the move to be accepted by KiCad.For the rest, the intention of your post is not entirely clear to me. Are you attempting to avoid clearance violations in all situations, or are you looking for a way to force to allow clearance violations?
Unexpected offset with simulation in kicad/ngspice.  - Page 1
Forum section: electronics / general

author: implor
author_rank: Regular Contributor
timestamp: September 29, 2025, 07:25:42 am
content: Hi.I'm trying to do a 0-3.3V to 4-20mA converter. It kindoff work but i'm getting an offset and I don't understand why.All models are from the built in libs.My question is if this is a "spice issue" or a real problem?

author: Doctorandus_P
author_rank: Super Contributor
timestamp: September 29, 2025, 08:17:05 am
content: With:Schematic Editor / Inspect / simulation / Simulation / New Analysis Tab / OP - DC Operating PointKiCad prints all DC voltages and currents in the schematic.I assume there is some error in the parameter of that V3 voltage source. Can you compare it with the other two?Or simply delete it, and replace it with a copy of one of the others. I'm still on KiCad V8 myself and can't open your schematic at the moment.On a sidenote, there is no need to add the backup folder with 6 copies of your project to the zip file.

author: implor
author_rank: Regular Contributor
timestamp: September 29, 2025, 08:27:55 am
content: I have now deleted V3 and made a new one (copy from V2).OP was very useful didn't know it existed (this is my first use of kicad for simulation).Sorry about the backup files. I just took the whole top folder.Here is the values for 0V input. Should give 4mA but it's 4.17mA.

author: implor
author_rank: Regular Contributor
timestamp: September 29, 2025, 09:04:57 am
content: I think I solved it.Default OPA had an attrochius 10m Voffset. Added worstcase for my opa (1.5) and we now have an acceptable 0.75% error rate.Thank anyway!PS. Upgrade to Kicad 9, did it myself a month ago and there is a number of nice-to-have that make it worth while.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: September 29, 2025, 11:42:20 am
content: There is also no need to add that "r=2k" You can add the values directly to the resistors, just like with any regular schematic.Also, it looks like U1 has an offset voltage of -4.54mVBut 20mA or 20.11mA is pretty good as comparison between ngSpice and a simple / hand calculation. Maybe you neglected the base current of the BJT's, or that offset voltage. But you have the tools to analyze it.There are also a few threads with each 20 to 30 working ngSpice examples on the KiCad forum, and they're showing different aspects of the simulations.
IPC-2581 - Page 1
Forum section: electronics / general

author: pdp7
author_rank: Newbie
timestamp: September 28, 2025, 03:44:08 pm
content: Hi, i am new here. If there is already a thread on this topic, please move it.I am interested in the support of the ipc-2581 format in KiCad, and specifically whether work is being done to add information for "component height".This is not the case in the current version 9.0.4, and I'm wondering if there is any work being done on it, or when I can expect it.Thanks

author: Benta
author_rank: Super Contributor
timestamp: September 28, 2025, 07:44:21 pm
content: Wrong forum. Try here:https://forum.kicad.info
Need guidance IN PCB design of Transimpedence cct - Page 1
Forum section: electronics / general

author: hasamsiddiqui@gamil.com
author_rank: Newbie
timestamp: September 10, 2025, 05:50:10 am
content: Hi,I am new to PCB design and need to complete this task within this week. I started working on it yesterday — first by watching some basic tutorials on YouTube, and then began building the circuit. However, I’m encountering some errors in the schematic diagram.Could someone kindly guide me on where I might be making mistakes and help me resolve them?Kind regardsHasham

author: hasamsiddiqui@gamil.com
author_rank: Newbie
timestamp: September 10, 2025, 06:03:31 am
content: Hi, I also attached the error list

author: Benta
author_rank: Super Contributor
timestamp: September 10, 2025, 10:24:53 am
content: On U3 (Which should be a J1) add a PWR_FLAG on each of the three wires.

author: xvr
author_rank: Frequent Contributor
timestamp: September 10, 2025, 10:30:31 am
content: Where is the input and output of your design?You need some kind of connectors for them.

author: Benta
author_rank: Super Contributor
timestamp: September 10, 2025, 11:21:04 am
content: Quote from: xvr on September 10, 2025, 10:30:31 amFor functionality yes.But KiCAD doesn't care.

author: golden_labels
author_rank: Super Contributor
timestamp: September 10, 2025, 12:37:00 pm
content: It’s worth explaining first, what you’re actually seeing.Electrical Rules Check (ERC) isa tool. As the name indicates, it checks if the circuit follows a set of rules. The purpose is to let you spot silly mistakes. The rules used are not infallible, and that works in both directions. The rules set can’t detect everything, and it can report on actually valid circuits. The tool only tells you: “hey, I noticed a rule is not observed, look here!”One of the rules is that power inputs should be connected to nodes, that are delivering power. But KiCad can’t know by itself, that something delivers power. You need to either connect that node to a power output or mark it with PWR_FLAG.Another of the rules detects, that you have suspicious “hanging” wires in the schematic. That kind of an error usually indicates the designer forgot to connect something, has left-overs from removing parts, failed to aim with mouse, or that something is misaligned and a wire isn’t connected (despite it visually appears to be). For example look at R4. You did draw a line that just goes beyond one of the pins and ends “inside” the resistor.edit: (extended explanation)A corrected example in the attachments. It’s meant to guide you in fixing issues with your own project. Not as a drop-in replacement for your schematic. In particular note I used different op-amp symbols.A word of additional explanation. At first it may appear weird, that you need to mark power lines as delivering power. What you may be missing is the actual purpose of symbols like “GND” or “+5V”. It’s written in plain sight, but easy to miss:Their role is similar to thebutton.
need some advices on a 6 layer Buck PFC pcb layout  - Page 1
Forum section: electronics / general

author: NORange
author_rank: Contributor
timestamp: August 07, 2025, 05:42:04 am
content: PCB design noob here referencing the power supply circuits of a TI 24W BLDC motor drive (https://www.ti.com/lit/ug/tiduas3a/tiduas3a.pdf?ts=1754495149016). I wonder if my KiCad schematic matches the original design from the provided link? As for the PCB, the first layer is used for the pfc controller stuff, the second layer for SGND, the third layer left empty, the 4th layer for the mains input power, the 5th layer for power ground, and the 6th layer is for some routing. How do I improve the current pcb design to rid it of potential issues like overheating and EMI? Thank you so very much in advance!Also, is there a way to properly place the heatsink on the mosfet?

author: Doctorandus_P
author_rank: Super Contributor
timestamp: August 07, 2025, 06:28:35 am
content: I find your use of empty rectangles instead of FET and diode symbols confusing, and it makes it harder to make a comparision. KiCad has a quite good symbol editor, and you can just load a copy of a default FET (or diode) symbol in the symbol editor and modify it (mostly adding an extra pin or so).For the rest, the original schematic seems reasonably well drawn. My default method for converting reasonably well drawn schematics is to useSchematic Editor / Place / Add Imageto load it, and then simply place the KiCad symbols simply on top of it. You can also scale the imported bitmap in KiCad so the symbol size is approximately the same as the KiCad symbols.
Silkscreen Text Revision Properties - Page 1
Forum section: electronics / general

author: Sac
author_rank: Contributor
timestamp: February 12, 2023, 08:32:04 pm
content: HiI'm stuck at linking a Silkscreen text property onto my PCB with Kicad. I want to Reference the Revision and Project to a text graphic. How do you do this?I was thinking something along the lines of Rev-%(Revision). I haven't had a mothers look through Google really.Pointers would be welcomeThanksSnowie

author: dkonigs
author_rank: Regular Contributor
timestamp: February 23, 2023, 06:53:27 am
content: The variable you put in the text field for revision is "${REVISION}".

author: Sac
author_rank: Contributor
timestamp: July 29, 2025, 02:56:51 am
content: Thanks......well that was easy
Change font size of all schematic ref designators and part names? - Page 1
Forum section: electronics / general

author: Circlotron
author_rank: Super Contributor
timestamp: October 05, 2025, 11:07:17 am
content: Is there a way to change the font size of all schematic reference designators and part names in one hit?

author: Psi
author_rank: Super Contributor
timestamp: October 05, 2025, 12:05:19 pm
content: Not that I'm aware of, but don't quote me.This also implies no.https://forum.kicad.info/t/find-select-similar-items/12897If the first response is correct and data is just stored as text files you could probably do it manually, but backup your project first in case you change something you're not supposed to or get something out of sync. And obviously don't edit anything while Kicad has the file openhm.. Does this help at all? (from url above)

author: 2N3055
author_rank: Super Contributor
timestamp: October 05, 2025, 12:53:00 pm
content: In Kicad 8 and 9 you have Edit Text and Graphic Properties in Edit menu.There you can set all kinds of things..

author: Doctorandus_P
author_rank: Super Contributor
timestamp: October 05, 2025, 04:17:27 pm
content: Quote from: 2N3055 on October 05, 2025, 12:53:00 pmAlso in KiCad V6 and V7. The screenshot shown by Psi has the old icons with the Coccinellahttps://en.wikipedia.org/wiki/CoccinellidaeIt looks even older, maybe that menu is from V4.Below a more modern screenshot from KiCad V8, and as you can see, KiCad has added quite a lot of options since back then.

author: Circlotron
author_rank: Super Contributor
timestamp: October 05, 2025, 08:49:31 pm
content: Okay then. Looks like I have to set the font details before I start drawing, not halfway along. That means I actually have to plan ahead…

author: Doctorandus_P
author_rank: Super Contributor
timestamp: October 05, 2025, 10:42:14 pm
content: Quote from: Circlotron on October 05, 2025, 08:49:31 pmNo. The schematic editor also has thisEdit Text and Graphics Propertieswindow in which you can change font, size and line thickness of texts.
Schematic Review: 12V DC Motor Controller - Page 1
Forum section: electronics / general

author: floobydust
author_rank: Super Contributor
timestamp: August 31, 2025, 05:56:02 pm
content: Quote from: lemm on August 31, 2025, 01:12:57 pmI was going to say it will blow up, you have the +12V sense resistor connecting to +3.3V
9.0.2 on Mint Mate - can't select text - Page 1
Forum section: electronics / general

author: Circlotron
author_rank: Super Contributor
timestamp: May 11, 2025, 12:24:52 pm
content: Just started fiddling around with KiCad version 9.0.2 the other day so I'm a complete beginner with this package. Have drawn hundreds of pcbs over the years though.Anyhoo... I put a random bit of text on the top silk screen layer and now I cannot for the life of me select it to edit it or move it in any way. Ordinary components select just fine. Is there some special way to select text?

author: Doctorandus_P
author_rank: Super Contributor
timestamp: May 11, 2025, 01:18:54 pm
content: In the lower right corner of the PCB Editor, there is a selection filter, and the checkbox for those items must be on for that sort of items to be selectable.Another option is that there are multiple overlapping items. In that case just press and hold down the mouse button for about one second. Such a long click opens a context menu which lists all items under the cursor, and you can select an item from the menu.

author: Circlotron
author_rank: Super Contributor
timestamp: May 11, 2025, 10:59:07 pm
content: There is no selection filter where you describe, and I can’t find it anywhere. Looked all through the menus too. Maybe they have hidden it somewhere on this latest version?And maybe a related problem- if I select and then lock a component, after that I am unable to select it to unlock it! The Lock and Unlock icons both stay greyed out. Edit Undo is the only way.Edit -> Okay, I've swallowed my pride and am now reading the instructions... I see the selection filter is a panel, not one of those small buttons. When I get home I'll try it out.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: May 12, 2025, 07:41:55 am
content: This is what it looks like, it's pretty obvious:There are at least two causes for it not being visible. One reason is:PCB Editor / View / Show Appearance Manageris off. When the PCB editor window is very small, it's also possible there is not enough room to show all items of the Appearance Manager. In that case you can attempt to grab some horizontal resizers in the Appearance Manager. These resizers are not really visible, but the mouse cursor changes when you hover over them.

author: Circlotron
author_rank: Super Contributor
timestamp: May 12, 2025, 11:21:26 am
content: Yes, I found it a bit before you posted. Thank you for your patience...
Kicad V9.0.1 is available. - Page 1
Forum section: electronics / general

author: djsb
author_rank: Super Contributor
timestamp: March 30, 2025, 07:14:34 am
content: https://kicad-downloads.s3.cern.ch/windows/stable/kicad-9.0.1-x86_64.exe

author: Doctorandus_P
author_rank: Super Contributor
timestamp: April 04, 2025, 06:28:40 pm
content: KiCad version numbers have two dots. So it's V9.0.1The first number is the mayor version, the second number is for minor changes (There was a V5.1, but as KiCad is now on a yearly release cycle, the second digit is unlikely to change from 0 again). The third number is for bug fix releases, there should never be any compatibility issues with upgrading bug fix releases. (Sometimes *&^%$#@! happens, and in such a case the version is pulled and a new bug fix release is released within a few days after the previous bug fix.So please try to add the extra dot to avoid confusion. (For some reason omitting the second dot is a mistake very many people make).

author: tooki
author_rank: Super Contributor
timestamp: April 04, 2025, 07:24:55 pm
content: Quote from: Doctorandus_P on April 04, 2025, 06:28:40 pmIndeed, and people don't realize it can be outright incorrect, because each group can be more than a single digit. For example, Mac OS X 10.1.1 is not the same as 10.11 (aka 10.11.0).

author: Monkeh
author_rank: Super Contributor
timestamp: April 04, 2025, 07:55:52 pm
content: And please, link to the release notes, not a direct download to an installer only relevant to some users.https://www.kicad.org/blog/2025/03/KiCad-9.0.1-Release/
FYI: KiCad 9.0 'apt' install is no longer supported for Ubuntu 20.04 - Page 1
Forum section: electronics / general

author: hamster_nz
author_rank: Super Contributor
timestamp: March 10, 2025, 02:12:23 am
content: Don't be like me and update your Windows laptop and designs to KiCad 9.0, then find out that you can't update your Linux desktop at home,However, you can try to run the sandboxed "FlatPak" version - however I'm getting some display weirdness in the PCB editor.

author: Whales
author_rank: Super Contributor
timestamp: March 10, 2025, 04:40:34 am
content: Ubuntu has been breaking so many things with their flatpak push. From the user's perspective it's just as annoying as Windows Store Apps.May I suggest the kicad PPAs? This bypasses Ubuntu's flatpak and gets the packages straight from the kicad devs. Details are on this page:https://www.kicad.org/download/linux/To quote them:Quote

author: radiolistener
author_rank: Super Contributor
timestamp: March 10, 2025, 05:28:12 am
content: I upgraded Kicad to 9.0 with apt upgrade from bookworm-backports/main and at a glance it works ok:Code:$ apt-cache policy kicadkicad:Installed: 9.0.0+dfsg-1~bpo12+1Candidate: 9.0.0+dfsg-1~bpo12+1Version table:*** 9.0.0+dfsg-1~bpo12+1 100100 https://deb.debian.org/debian bookworm-backports/main arm64 Packages100 /var/lib/dpkg/status6.0.11+dfsg-1 500500 https://deb.debian.org/debian bookworm/main arm64 Packages

author: alfrede
author_rank: Newbie
timestamp: March 10, 2025, 08:04:17 am
content: Hi in the Kicad Website there is a seperate Ubuntu Site for that:https://www.kicad.org/download/details/ubuntu/i hope it will help you.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: March 10, 2025, 01:03:30 pm
content: Apart from alfrede's remark. Ubuntu V20 is pretty old. I guess it's retired, but I have not looked up the details. KiCad is moving on, and uses newer versions of libraries for a bunch of software components. Those two things don't mix well. You're probably better of by first updating Ubuntu to a newer version.

author: themadhippy
author_rank: Super Contributor
timestamp: March 10, 2025, 01:55:11 pm
content: QuoteNot quite ,end of may it gets pensioned off. Kicad 9 is working fine here on 24-04,cant remember wot i did to to get it,so it must have been painless.

author: JMK
author_rank: Contributor
timestamp: March 11, 2025, 01:34:14 am
content: Quote from: themadhippy on March 10, 2025, 01:55:11 pmThe thread is about 20.04. Your comment is about 24.04. Quite a difference in OS's.

author: bitwelder
author_rank: Super Contributor
timestamp: March 11, 2025, 02:27:27 pm
content: Also looking at the PPA, athttps://ppa.launchpadcontent.net/kicad/kicad-9.0-releases/ubuntu/dists/I see that the minimum is jammy i.e. Ubuntu 22.04, so I'd guess 20.04 (focal) is quite out of scope for Kicad 9.0

author: abeyer
author_rank: Frequent Contributor
timestamp: March 11, 2025, 05:19:46 pm
content: Quote from: bitwelder on March 11, 2025, 02:27:27 pmIt's almost out of scope for even basic security patches unless you pay Canonical for extended support. The standard support on LTS releases runs for 5 years, so will be wrapping up in April 2025.
VRML has an extra polygon layer on back - Page 1
Forum section: electronics / general

author: koeg
author_rank: Newbie
timestamp: January 19, 2025, 08:21:26 pm
content: Hi, I have this keyboard project(https://github.com/KOEGlike/mito-pcb) that I'm working on right now, but when I export a VRML, it appears that there is a second layer of mesh on the back side (see GIF), which hides some parts of the components.I can't remove this layer by hand because I use this extension(https://github.com/30350n/pcb2blender) to import the KiCad board to blender with materials, and it would be a hassle to mess with an already textured modelQuick info:- I used blender4.3 to view the file- I used KiCad nightly to export the VRML- here is the [blender project and VRML file](https://github.com/KOEGlike/mito-blend)- I know the VRML is the problem because when I import the raw VRML file without the fancy extension/add-on I mentioned earlier, it still looks like this, this is what is show in the GIF, and it shows the same extra layer in freecadSteps to reproduce1. Clone the repo2. Open the project in kicad 93. Export the VRML from PCB editor4. View it in blenderKiCad VersionCode:Application: KiCad x64 on x64Version: 9.0.0-rc1-329-g89a50a3dcf, release buildLibraries:wxWidgets 3.2.6FreeType 2.13.3HarfBuzz 10.0.1FontConfig 2.15.0libcurl/8.10.1-DEV Schannel zlib/1.3.1Platform: Windows 11 (build 22631), 64-bit edition, 64 bit, Little endian, wxMSWOpenGL: ATI Technologies Inc., AMD Radeon PRO Graphics, 4.6.0 Compatibility Profile Context 24.7.1.240618Build Info:Date: Jan 3 2025 06:18:01wxWidgets: 3.2.6 (wchar_t,wx containers)Boost: 1.86.0OCC: 7.8.1Curl: 8.10.1-DEVngspice: 43Compiler: Visual C++ 1942 without C++ ABIKICAD_IPC_API=ONLocale:Lang: en_USEnc: UTF-8Num: 1,234.5Encoded кΩ丈: D0BACEA9E4B888 (sys), D0BACEA9E4B888 (utf8)

author: djsb
author_rank: Super Contributor
timestamp: January 23, 2025, 06:49:43 pm
content: Have you tried posting this on the official forum?https://forum.kicad.info/And then maybe posting it as a bug depending on the feedback from other users?Good luck.