hybridfree/eevblog-posts huggingface dataset:
Software for domestic electrical installations - Page 1
Forum section: electronics / general

author: nilium
author_rank: Contributor
timestamp: August 21, 2013, 02:28:55 pm
content: Hello all,I was wondering if people had any insights for a software package for generating schematics of domestic electrical installations (circuit breakers, wall outlets, etc.). I'm not sure Altium has capabilities beyond electronic circuits.Many thanks,NV

author: Mechatrommer
author_rank: Super Contributor
timestamp: August 21, 2013, 04:53:38 pm
content: for pro or industrial grade design, the company where i were was using AutoCAD, you may find general purpose free CAD that can do the job. for personal use, i prefer pencil, eraser and paper.

author: nilium
author_rank: Contributor
timestamp: August 21, 2013, 11:12:24 pm
content: Thank you. I will check out AutoCAD Electrical. I've been using regular AutoCAD to draw boxes and stuff, but it would be nice to have something more pertinent. I would appreciate any other ideas (Windows/Mac/Linux)!NV

author: Smokey
author_rank: Super Contributor
timestamp: August 21, 2013, 11:50:59 pm
content: I've seen Autocad used a lot for machine tool wiring documentation. That works really well.You don't really need anything special though. Any vector graphics package would work. You only have to draw whatever symbols you need once, then cut and paste and connect with lines.I've made custom symbols for our schematic capture program that I've used for wiring diagrams, but it probably would have been faster to just draw them as line drawings.

author: free_electron
author_rank: Super Contributor
timestamp: August 21, 2013, 11:55:06 pm
content: Square-D and Siemens have drawing programs that include all their products. Legrand also has something like than.

author: Kremmen
author_rank: Super Contributor
timestamp: August 24, 2013, 11:50:46 am
content: Quote from: nilium on August 21, 2013, 11:12:24 pm+1 AutoCAD Electrical. Done some industrial electric drawings with it and that is definitely the way to go. There is a learning curve and it will be a bittersweet experience in its initial complexity, but IMO worth it if you have the chance. You can of course do drawings with a pencil on lined paper, but ACAD E will be a different world in its support for the design workflow and design documentation.
Pattern for testing etching - Page 1
Forum section: electronics / general

author: brainwash
author_rank: Frequent Contributor
timestamp: August 08, 2013, 01:32:09 pm
content: Does anyone have some kind of a test board with progressively finer pitch and thinner traces? I'm looking for something like this to test the best the limits on the toner transfer method so it should be something a bit uniformly distributed. I'll eventually make one myself if no one has something.Edit: found something, but it's not complete:http://electronics.stackexchange.com/questions/23089/pcb-test-patterns-to-assess-etch-quality

author: Len
author_rank: Frequent Contributor
timestamp: August 08, 2013, 08:40:32 pm
content: On a recent Amp Hour, Laen of oshpark.com (@laen) talked about layouts he uses to test PCB manufacturing services. I don't know if he's published those layouts, but I bet he'd share them if you ask.

author: brainwash
author_rank: Frequent Contributor
timestamp: August 08, 2013, 09:34:11 pm
content: Cool, I'll have to read the transcript.In the end I just used the link above to print the test pattern. For my printer the lower limit is 0.1 mm traces and 0.2mm spacing.Detailed here:http://hackcorellation.blogspot.de/2013/08/etching-boards-for-smd-follow-up-on.html
Standards for PCB dimentions(pads, routes, etc.) , etc. - Page 1
Forum section: electronics / general

author: glatocha
author_rank: Regular Contributor
timestamp: June 28, 2013, 03:25:13 pm
content: Hi all,Is there (where?) a standard for a dimentions in PCB design?For example I am doing (I think we all do) a lot of own libraries/packages. And for example what pad size should I use?I don't want to use 0.55mm if 0.57 is some standard, and so on.Same for drilling. If I use 0.7 and 0.8 is a standard, then will have problems later in manufacturing.Is there any ISO or IEEE something. Would be nice if free available?RegardsGL

author: Niklas
author_rank: Frequent Contributor
timestamp: June 30, 2013, 07:36:05 pm
content: Have a look at the LP Viewer:http://www.mentor.com/pcb/downloads/lp-viewer-download/

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: July 03, 2013, 05:22:22 pm
content: Quote from: glatocha on June 28, 2013, 03:25:13 pmPlenty, but standards exist for specific formats, such as VITA, CompactPCI. Look at Eurocard for example: IEC-60297-3. So if you are designing PCIx card - of course you should not make it on 3mm thick laminate cuz it won't fit into slot.What are you making?For power power supply standards for safety, track with, clearances etc will be only ones of concern.

author: glatocha
author_rank: Regular Contributor
timestamp: July 03, 2013, 10:25:26 pm
content: Nothing like PCI or some sort of that.95% small hobby style uC boards.For power supply would be nice to have also, as I need to make one board soon

author: poorchava
author_rank: Super Contributor
timestamp: July 04, 2013, 07:07:34 am
content: You can take a look at IPC-7351 standard. It defines land patterns for nearly all types of packages so that the resulting solder joint is according to IPC standards (sorry, I can't recall the exact standard number). Altium designer has a wizard that will create such footprints for you. Obviously you can tweak them later (for example to get soldermask bridge between qfp pads).

author: Mengano
author_rank: Newbie
timestamp: July 14, 2013, 07:06:45 pm
content: Some useful IPC standards for the PCB designer:IPC-2221 Generic Standard on Printed Circuit Board Design (recently updated, not free, but available at a discount for designers. Probably can find an older copy or two floating around on the net)IPC-6012C Qualification and Performance Specification for Rigid PCBs (this is where "Class 1, 2, and 3" are defined)IPC-7351 already mentioned by others. It's overdue for an update, and one is coming, but it sounds like there is still a lot of debate between the committee members, Rev C is the next version coming)
Closed: Minimum Solder Mask Sliver - Page 1
Forum section: electronics / general

author: selkathguy
author_rank: Unknown
timestamp: June 28, 2013, 07:19:32 pm
content: EDIT:Quote from: selkathguy on July 01, 2013, 01:11:17 pmI'm trying to route pins of a TQFP-48 package, but I'm running into default design rule violations for "Minimum Solder Mask Sliver". I don't want to shrink the solder mask too much, but I also still want to keep solder mask between the pins if at all possible (I'm thinking of using paste and hot air to reflow the chip, and I really don't want shorts). The pin pitch is about 0.5mm, and the software complains that the sliver is only ~3.2 mil wide. I've googled and searched on the forums here and haven't really gotten a good answer that I was looking for. Some say that it wont be a problem, some say that you should just leave the solder mask off for each row of pins (because the mask can flake off or something during soldering and cause problems). Does anyone have any advice or pointers on what I should do or what the real minimums are? What capabilities do PCB manufacturers (e.g. PCBCart) typically have in terms of these tolerances? Can't find information on websites about it. Thanks in advance!

author: selkathguy
author_rank: Unknown
timestamp: July 01, 2013, 12:58:54 pm
content: For a 0.5mm pitch like this, should I leave the solder mask off in 4 swaths around each side of pins? Or should I keep the slivers even though they're <10 mil wide? I'm not familiar with how well such thin pieces of solder mask can be manufactured.

author: selkathguy
author_rank: Unknown
timestamp: July 01, 2013, 01:11:17 pm
content: Nevermind, I think I've found another thread that answers my question. I'll just have to go with dry film solder mask, from what I hear. If this is incorrect, please PM me. For now I will close the thread.
Multisim 2K8RAM - Page 1
Forum section: electronics / general

author: Gatos De La Muerte
author_rank: Contributor
timestamp: June 15, 2013, 06:43:10 pm
content: Hey, I'm new to this forum and wonders if there are any Multisim users here?I'm working on a small project were I'm using the 2K8RAM component as storage for a program.The project is a small 8bit MCU/CPU, I'm using the 2k8Ram as a program storage.My problem is that when I start the simulation the 2k8Ram starts with all addresses is in an unknown state, and this is causing some problem when I try to load my program.I've solve this problem by programming a 8051 to set all addresses to 0 and then load my program,but this takes 5 minutest to clear and load a 24 instruction (4 commands) program...I could use the 8051 to give out the commands, but I rather have it just load the program in ram and then "virtually" remove itself.I'm wondering is there is an other component or an other way to load a program in to a blank memory?The point of this project is just to learn how a simple 8bit CPU might be constructed.If I give the instructions to the circuits it runs fine, but I takes a lot of time to give 6 instructions (with is actually just on command) manualy and that is preventing me from getting further in the design, because1. if I do it manually and there is a small error I have to stop the simulation, fix it and then "reprogram it"2. I had to re-do a lot of things to try and "debug" the circuit while the error was actually the ram being in an "unknown state" (rocky mistake) .Side note:I'm doing this at home so there might be something that I'm missing/doing wrong and I don't know people that can help me, that's why I'm asking for help in the internet.I'll upload the circuit if it's needed, but I prefer not to because it's in a lot of small pieces right now.And any info about designing a CPU would be greatly appreciated
Selective Assembly - Page 1
Forum section: electronics / general

author: pankajp
author_rank: Newbie
timestamp: June 10, 2013, 05:42:53 pm
content: Hi,i am new to PCB Assembly.I am told that to assemble PCB in attachment (USB and Phone jack), selective assembly is required. Can someone, in this forum, let me know what is "Selective Assembly" line?Any information and equipment vendor suggestion in this regard is appreciated.thanksPankaj

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: June 11, 2013, 08:43:46 am
content: I think they mean selectively soldered - using a machine that can put a small 'fountain' of solder at specific places on the PCB.Of course it could also be hand-soldered.

author: nctnico
author_rank: Super Contributor
timestamp: June 13, 2013, 06:55:43 pm
content: Usually they cover the holes with fast curing heat resistant rubber or kapton tape to prevent solder flowing into holes or onto pads where it shouldn't. The through hole parts are often soldered by hand.
x - Page 1
Forum section: electronics / general

author: StevenWhitney
author_rank: Newbie
timestamp: October 31, 2013, 01:42:22 am
content: x

author: Thor-Arne
author_rank: Unknown
timestamp: October 31, 2013, 10:21:31 am
content: Exactly how are you trying to make the symbol for this?The library editor shouldn't make errors like that.

author: c4757p
author_rank: Super Contributor
timestamp: October 31, 2013, 04:02:09 pm
content: That tool is not checking to make sure that what you've entered is compliant with KiCad restrictions. Note that the file format is space-delimited, and you have used spaces in pin names. That's illegal. Change "LE ED1" and "OE ED2" to LE_ED1 and OE_ED2 or similar and it works. (You'll notice that KiCad automatically changes space to underscore in pin names.)The fact that it waits until the very end to barf is proof of what I've suspected for a long time: nobody working on KiCad knows how to write a damn parser...What was wrong with the pin spacing? Do you mean the spacing between pins and names? That's the quite poorly documented "skew" field in the Component Properties box.

author: tehmeme
author_rank: Regular Contributor
timestamp: October 31, 2013, 04:09:14 pm
content: This works.Please check for mistakes and edit as needed.Edit: The tilda ~ in KiCad library editor denotes the logical "NOT" or "active low" symbol.It should show up correctly when you import it into kicad.

author: Thor-Arne
author_rank: Unknown
timestamp: October 31, 2013, 06:48:10 pm
content: Pin spacing?The library editor defaults to 50 mils (1.2700 mm)."Normal" pin spacing in KiCad libraries is 100 mills, so add the pins with two grid-dots between.
Problems with Dynamask 5000 (Dry Film Solder Mask) - Page 1
Forum section: electronics / general

author: farrell
author_rank: Contributor
timestamp: June 13, 2013, 05:10:08 pm
content: I'm been trying to get it working right, but always end up with bubbles.I etch (sodium persulphate) and tin plate (MG Chemicals Liquid Tin) my board. I wash it thoroughly, then dry it thoroughly (including a little hot air to evaporate anything hidden.) Then I cut a piece of mask to size, peel off the dull side, and stick it down to one end of the board. I run it through my laminator and make sure the mask only meets the PCB at the rollers. I've got that down to where I don't get wrinkles.This is where the problems start. I run the board through the laminator a few times, each time in a different direction, and the mask starts to adhere to the board better each time. After the third or fourth pass bubbles appear and the green material clumps under the bubbles. If I only do two passes, the mask isn't stuck down very well (I can see many places where the mask isn't stuck to the PCB by looking at the back side of my single-sided board...)My laminator only has two "temperatures" labeled 5mil and 10mil. 5mil mode seems to work best. If I use the 10mil mode it gets really hot and the green film starts to ooze out after just two passes. In 5mil mode it takes about five passes to get the green film to ooze out. I'm fairly sure that's a bad thingIs my lamintor just too hot? Or maybe something else? I've watched a few YouTube clips of people using this stuff and it seems almost idiot-proof. I'm stumped.On a side note, all the video clips I've seen result in a high-gloss solder mask. Mine come out semi-glossy after I develop them. I've tried playing with the water/sodium carbonate ratio, and the exposure time, but they doesn't seem to have an effect. The mask is functional, but doesn't look like a typical solder mask.Thanks,-Farrell
Unusual PCB solder defect - Page 1
Forum section: electronics / general

author: djbird3
author_rank: Newbie
timestamp: April 10, 2013, 10:11:00 pm
content: I was looking through some junk boards today for a part and noticed something unusual about the T-Con board shown below. When I grabbed the board a few of the parts just came right off like they weren't even soldered. I started checking the PCB closer and noticed just about every part on the board could easily be knocked off the board including the 176 pin quad pack shown below.I've worked as a Tech for over 25 years and have seen my share of cold solder joints and corrosion problem caused by capacitors but have never seen this kind of problem so I figured I'd post it in the forum to see if anyone else has come across this or could explain what caused this defect. A close inspection of the board reveals that somehow oxidation formed between the copper solder pads and the solder itself resulting in the bond between the two to be weakened but what would cause this?...I'm thinking bad solder paste or maybe impurities in the copper cladding but I'm just guessing.~Don~

author: marshallh
author_rank: Unknown
timestamp: April 10, 2013, 10:18:24 pm
content: Probably a combination of early, unrefined lead-free processes and nickel plating coming off the copper base. (ENIG)

author: free_electron
author_rank: Super Contributor
timestamp: April 11, 2013, 01:33:07 am
content: definately nickel peeling...the board is clearly enig. the parts that fell off leave copper behind.they may have had conatminated copper before they applied the nickel.

author: nanofrog
author_rank: Super Contributor
timestamp: April 11, 2013, 02:42:19 am
content: Quote from: free_electron on April 11, 2013, 01:33:07 amThis is my suspicion as well.

author: mertsok
author_rank: Newbie
timestamp: June 07, 2013, 08:41:28 pm
content: I have also come across this type of problem for the first time. Anyone encountered this type of problem before? I think this might be soldering process issues.electronics assembly

author: KJDS
author_rank: Super Contributor
timestamp: June 07, 2013, 09:01:06 pm
content: I've not seen bad nickel on a board before, but I've seen bad nickel plating on aluminium housings where the plating would just peel off due to poor process control at the plating shop.
Header pin hole diameter - Page 1
Forum section: electronics / general

author: headingwest
author_rank: Newbie
timestamp: May 22, 2013, 04:35:22 am
content: Hi All, I'm putting together my first PCB.At one edge are some header pins. I've downloaded a number of datasheets but can seem to get a standardised hole diameter that would work well.Does anyone have an opinion on a good generic hole size for these connectors?Thanks.

author: mariush
author_rank: Super Contributor
timestamp: May 22, 2013, 05:18:37 am
content: If you mean the standard 2.54 mm (0.1") spaced pin header, seems that diameters range between 1 and 1.15 plus some tolerance.Ex seehttp://www.farnell.com/datasheets/1670824.pdfhttp://www.farnell.com/datasheets/1442180.pdfhttp://www.farnell.com/datasheets/819778.pdfhttp://www.harwin.com/include/downloads/drawings/M20-995.PDFSo use whatever's standard above 1.1mm or so?

author: poorchava
author_rank: Super Contributor
timestamp: May 22, 2013, 11:32:26 am
content: I use 0.9 for a loose fit and 0.8 for tight fit.

author: free_electron
author_rank: Super Contributor
timestamp: May 22, 2013, 02:53:58 pm
content: 45 mils hole works well.

author: cthree
author_rank: Frequent Contributor
timestamp: May 28, 2013, 04:55:36 pm
content: I use 40mil which is nominal I thinks.
Need Help Finding a decent software package. - Page 1
Forum section: electronics / general

author: blewisjr
author_rank: Frequent Contributor
timestamp: May 27, 2013, 05:47:12 pm
content: Hello Everyone,I am sure this has been asked many times. Right now I just finished up my first project on a breadboard. Yey!!!It has come time that I need to move it to a PCB and enclosure. I really do not want to etch my own boards so I was thinking about either perfboard or just getting a few fabed as I am going to make at least 3 of these devices.To do either of these I am going to have to make a schematic and board layout. I have only ever done 1 schematic and it was just toying around it was nothing real per say. I have never laid out a board before.I have tried both DipTrace and Eagle. DipTrace is nice and I like Eagle as well. My biggest issue with DipTrace is the huge lack of components where with Eagle I can at least get the right SPST buttons. Either way I am going to have to make a few components as even MicroChip does not have design files I can export for the chip I am using :S.The biggest issue I have with both of these packages is the fact that they are not free but I believe for this project the free versions of both are good enough.I guess what I am looking for is some tips and advice that can point me in the right direction to both making the schematic, to laying it out, as well as recommendations on software that would work best for someone with horrid design skills. You should really see what this breadboard looks like lol.

author: hlavac
author_rank: Frequent Contributor
timestamp: May 27, 2013, 06:02:59 pm
content: For practical reasons I would recommend Eagle over Diptrace. Most PCB manufacturers can make boards directly from Eagle files and there are lots of component libraries available.It is however easier than before to convert footprints between packages as there seems to be a movement toward documented XML formats lately.There are even some interesting attempts at cross-package libraries likehttps://circuithub.com/
Burned PCB Pad - Page 1
Forum section: electronics / general

author: baElectronic
author_rank: Contributor
timestamp: February 05, 2013, 06:08:40 am
content: Hi,I'm repairing my plasma TV, and the pad under a surface mount mosfet is charred on the Y-Sustain. I'm reluctant to reuse the board, but a replacement Y-Sus is $100+. I read online that I can scrape down to good board material and refill with an epoxy/fiberglass mixture:http://electriciantraining.tpub.com/14186/css/14186_128.htmI've attached pics of the front side and the back side of the board.

author: Psi
author_rank: Super Contributor
timestamp: February 05, 2013, 06:42:31 am
content: I would give it a really good clean with solvent, then give the area a sand with 400 grit sandpaper and see how it looks.That will tell you if the burn marks are just on the surface or not.If it looks impossible to solder a new mosfet in you may have to mount it on an external heatsink and run short wires to the pcb.

author: baElectronic
author_rank: Contributor
timestamp: February 05, 2013, 07:07:20 am
content: Quote from: Psi on February 05, 2013, 06:42:31 amThe burn is not a surface-level burn; I've scraped away some of the burned PCB material already. The blackened portion in the middle of the pad is where I scraped. I actually jumped the gun a bit and soldered on a new mosfet just fine without scraping away ALL the burned material, so I anticipate that I'll have a burning odor when I fire up the TV. I believe that the mosfet can be reattached after I scrape away the remaining burned material, but I was thinking about whether I need to fill the leftover crater.

author: Zapro
author_rank: Contributor
timestamp: May 22, 2013, 07:27:42 pm
content: You won't have a burning smell after replacement of the part, worst case it stops smelling after a couple of weeks.It can be a problem when the charred PCB material becomes conductive, and then it will give you problems, maybe start smoking and parts blowing up.// Per.
Kicad code review, after a quick poke around in the source. - Page 1
Forum section: electronics / general

author: HackedFridgeMagnet
author_rank: Super Contributor
timestamp: April 25, 2013, 02:25:40 am
content: I just had a look at some of the Kicad source code.http://bazaar.launchpad.net/~kicad-testing-committers/kicad/testing/filesIt's much better than I have been led to believe. Although I only looked at the PCBnew.exeSome of the good things were:It uses STL vectorsI only counted one char* in the files that I saw.There was quite a bit of explanatory commenting.It uses lots of functions to neatly encapsulate logical steps, with meaningful function namesThe smaller functions seem to pass in all the necessary parametersI didn't see any really bizarre or obscure c++ stuff that would be perfectly legal but is better not used.But:There does seem to be some newer code classes mixed with some older ones.Many files have the "class_" filename prefix such as "class_pcb_layer_widget.h" these use the .h and .cpp file types in the traditional manner.The other ones are all over the place.eg. "block.cpp" has a member function for class PCB_EDIT_FRAME and a member function for class DIALOG_BLOCK_OPTIONS."editedge.cpp" also implements a function of the class PCB_EDIT_FRAME??!This does need a reorganisation. I didn't actually find the declaration of these classes.Overall I think the code quality seems pretty good.I have seen far far worse, and for a large legacy O/S project I couldn't really expect better.
DesignSpark PCB 5.0 has been released - Page 1
Forum section: electronics / general

author: Bloch
author_rank: Unknown
timestamp: April 13, 2013, 01:15:06 pm
content: I am not sure why they did get the date wrong16/04/2013 - Version 51.Online DRC(real-time Design Rule Check)2.Schematic Buses(combining multiple signals into a Bus)3. Installer improvements:dedicated (version-dependent) folders preserving Library folders when uninstalling preserving registry settings when uninstalling (for automatic activation of new version) improved messaging4. Reorganised Tutorial links and Start Menu shortcuts
Solder Mask and PCB Heat Sinking - Page 1
Forum section: electronics / general

author: beaker353
author_rank: Unknown
timestamp: March 28, 2013, 01:05:08 am
content: This maybe more of an academic question than a practical one. I have a project that I plan on using some area on a PCB to act as a heatsink for a TO-220FP package (an St Micro LM317P). My calculations tell me my heat dissipation don't require a heatsink, but as I have the extra PCB space, why not add some more margin. I have just a tad under a square inch on each sides of the PCB that I plan on using, stitching the two sides together with a bunch of vias for heat transfer to the back side (also seen the trick of using 22GA solid copper wire though the vias and soldering on both sides to increase the heat transfer efficiency). My question is whether or not having solder mask over the copper would have an appreciable effect on the heat dissipated from the copper to the air I know it's important to keep the mask off where the package touches the PCB, but is there really a difference for the rest of the copper pads to be mask free? Thanks!- EM

author: JuKu
author_rank: Frequent Contributor
timestamp: March 28, 2013, 08:03:32 am
content: Do you have any reason not to take off the mask? I know I'm warmer with my sweater on than off...

author: marshallh
author_rank: Unknown
timestamp: March 28, 2013, 09:03:23 pm
content: Either use a proper heatsink or design in a switching reg and make heat a non-issue.

author: SeanB
author_rank: Super Contributor
timestamp: March 29, 2013, 10:12:53 am
content: More important is if there is air flow over that area. The biggest heatsink in an enclosed box has very little heat transfer. Make a hole and mount it with a nut and bolt to the board, and use a thermal pad between the device and the board as well, this will make a bigger difference than solder masking. The board does not need the solder mask removed where the device mounts either, as it is an insulated device in any case, and the mask is going to be as good as the board in heat transfer. If you have the space a U shaped heatsink would be a better idea, it does not have to be that big for low power if the bare device alone is capable, it just makes it run cooler and more reliably.

author: mrflibble
author_rank: Super Contributor
timestamp: March 29, 2013, 10:58:31 am
content: Unless you're going to heat up your PCB to several thousand Kelvin, the main chunk of heat transport is going to be convective. So as SeanB pointed out already, air flow is much more important to worry about that soldermask or not.The main reason for my PCBs to keep the soldermask off is so I can add big solder blobs to the trace. Mainly to increase current carrying capacity and as a bonus you get a bigger thermal mass. This thermal mass helpssomewhat... but you still have to get rid of the heat, so either heatsink or forced air flow (or both).
(LT)SPICE wizards? What is wrong with this model? - Page 1
Forum section: electronics / general

author: c4757p
author_rank: Super Contributor
timestamp: March 16, 2013, 09:01:25 pm
content: (Posting here because I guess it's the closest match.)I was hoping someone here would be able to find the problem. I downloaded a model from TI for the LM5050 power supply OR-ing controller. It's a PSPICE model. I've had excellent luck in the past using PSPICE models in LTspice (even ones that claimed to use advanced PSPICE features), but this one has me stumped.Whenever I include this model in LTspice, I always get an error: Can't find definition of model "x", wherexis the name of whatever node is connected to "IN". I'd include a schematic, but the schematic doesn't matter one bit - it does this even if the LM5050 is the only thing in the file, with GND grounded. Since it appears to be treating a node like a model name, I am assuming it's a syntax error somewhere, but to my eyes the file looks fine. Any ideas?(Also included the .asy file I prepared if anyone wants a quick way to pop this into LTspice, though I figure whatever problem is there is best solved by looking at the model text.)

author: osf31
author_rank: Newbie
timestamp: March 26, 2013, 07:43:17 pm
content: Hi,You can try to rename the symbol file from "LM5050-1asy.txt" to "LM5050-1.asy"Then edit with LTspice the symbol attribute and change:*Line Prefix "U" to "X" ( for subcircuit)*ModelFile "LM5050-1.lib" to "LM5050.txt" (correct .txt)osf31

author: c4757p
author_rank: Super Contributor
timestamp: March 26, 2013, 07:48:33 pm
content: Quote from: osf31 on March 26, 2013, 07:43:17 pmI renamed it for posting to the forum because of the file extension restrictions.Quote from: osf31 on March 26, 2013, 07:43:17 pmYup, that's it! Somewhere in my SPICE self-taught "education", I seem to have missed the U/X distinction.Fixed. Thank you!
Altium Keyboard Shortcut Issues? - Page 1
Forum section: electronics / general

author: strobot
author_rank: Contributor
timestamp: July 10, 2013, 07:28:59 pm
content: I'm having a couple issues with Altium shortcuts:Seeing all the shortcuts?Right now, I haveView->Workspace Panels->Help->Shortcutsturned on to help me learn the various keyboard shortcuts.When I go into Interactive Routing mode (P->T) in a PCB document, the Shortcuts panel shows the relevant shortcuts, but the cursor turns into a crosshair for placing the traces and when I try to mouse over the Shortcuts panel, it turns transparent and doesn't allow me to click anything in it. There is a scrollbar in the Shortcuts panel that I would like to access so that I can see all the available shortcuts. Is there any way to scroll the shortcuts panel while in Interactive Routing?Rebind Interactive Routing Shortcuts?The second issue is that some of the shortcuts in Interactive Routing only apply to keyboards with a numeric keypad. For example: Next Layer and Previous Layer are bound to + and - on the numeric keypad. I'd like to bind these to something different, so that I can access them easily on a laptop keyboard without a numeric keypad. How do I go about doing this?I read this blog post, but I can't find those commands when I click the Browse... button in the Edit Command dialog.http://altiumpcbdesigner.blogspot.com/2012/11/custom-shortcut-keys.htmlSwitch Layer for Current Trace?The "L" shortcut under Interactive Routing for Switch Layer for Current Trace doesn't seem to do anything. I place part of a trace on the top layer, then press L, and all I hear is the bell error sound. Nothing happens. Whats the deal? Top Layer and Bottom layer are enabled in the View Configurations layer manager.EDIT: crap, please delete. I have posted in the correct, Altium subforum
Is There an Engineering Talent Crises in the US? By Ed Goldman, Mentor Graphics - Page 1
Forum section: electronics / general

author: milliman
author_rank: Newbie
timestamp: March 21, 2013, 05:40:21 pm
content: Could this be due to a possible demographic shift in the industry? Read more and please leave your comments on the blog. -Stephaniehttp://go.mentor.com/2soc4

author: StevenB
author_rank: Contributor
timestamp: March 21, 2013, 06:45:32 pm
content: As an EE in the US, I have no problem with this.The #1 solution to this is higher pay, so it takes care of itself if the government doesn't tinker. By tinker, I mean (from the article): "Obviously every challenge presents opportunities and some of the solutions will come frompoliticaland business leaders".I always cringe when I hear of programs to increase issuance of green cards to bring in more engineers.
Eagle/Diptrace Licensing/Support models - Page 1
Forum section: electronics / general

author: luisr
author_rank: Contributor
timestamp: March 18, 2013, 01:04:27 pm
content: Hi there everyoneThis is a call for current license' owners of both packages, I wanted to compare them in terms of licensing and support.On the licensing department Diptrace seens to be a bit more clear when talking about it: minor updates are free and mayor updates only cost 25% of the current price... also upgrading the license to higher level only cost the price difference...In the case of Eagle I couldn't find info about cost of mayor updates or how much will it cost going from let's say Eagle Light to Eagle Standard... there's an upgrade option on the eagle website but since I don't have a license I can't go through the process to see how much will it costWondering if current owners that have upgraded their licenses can give some feedback (both packages)Regards

author: xygor
author_rank: Regular Contributor
timestamp: March 18, 2013, 09:55:42 pm
content: Had the same questions about eagle myself recently. Found info at a reseller site.Upgrade policy: pay the difference between what you have and what you want. cfhttp://www.eaglecentral.ca/eagle/9-eagle-central/58-eagle-upgrade-policyMinor updates I guess are free since there are no prices listed for that.Major upgrade prices are at the above link.

author: luisr
author_rank: Contributor
timestamp: March 18, 2013, 11:30:33 pm
content: Thanks for the link... according to that reseller upgrading from the previous mayor version (v5) will cost about 33% of the current price... also upgrading from v4 to v6 will cost about 67% of a new license... on the other hand Diptrace is a bit more flexible offering free upgrade to v2 for user that bought v1.5 after August 31, 2008Well... in terms of upgrade policies they are more or less at same level, although Diptrace seens to be more affordable at the end.I'm liking both packages so I will give them another try to both of themThanks
PCB Fab House capable of putting soldermask between 0.5mm pitch footprint? - Page 1
Forum section: electronics / general

author: luisr
author_rank: Contributor
timestamp: March 01, 2013, 04:52:47 pm
content: HiI'm evaluating using some 0.5mm Pin Pitch devices which, according to the datasheet of one of the devices I'm planning to use, would require a footprint with solder max expansion of max 0.05mm (0.002"). Even more due to pad size (0.3mm) there's only 0.2mm of clearence between the pads, so the solder mask between the pads will be very tiny 0.19mm at maxIs there any USA based PCB FAB House that can manufacture a pcb with such solder mask requirements and still be accesible for hobbyist?Thanks in advance

author: free_electron
author_rank: Super Contributor
timestamp: March 01, 2013, 08:16:33 pm
content: you'd have to go with dry resist probably.most pcb fabs should be able to do that. it's not so extraordinary.

author: luisr
author_rank: Contributor
timestamp: March 04, 2013, 10:20:27 pm
content: Quote from: free_electron on March 01, 2013, 08:16:33 pmThanks for anwsering... do you mean Dry Film Photoresist?

author: free_electron
author_rank: Super Contributor
timestamp: March 05, 2013, 01:27:01 am
content: dry film soldermask

author: luisr
author_rank: Contributor
timestamp: March 06, 2013, 10:26:15 pm
content: I will search info about it, but that sounds expensiveThanks...

author: Medo
author_rank: Regular Contributor
timestamp: March 11, 2013, 07:07:59 am
content: I have just checked few boards I have with 0.5 mm pitch components and they all do have solder mask between the pins.I got them made at OSH Park (http://oshpark.com/).

author: luisr
author_rank: Contributor
timestamp: March 11, 2013, 10:30:08 pm
content: Quote from: Medo on March 11, 2013, 07:07:59 amThanks I will have a look at their website
Scheme understanding - Page 1
Forum section: electronics / general

author: electro
author_rank: Newbie
timestamp: April 21, 2013, 01:49:58 pm
content: Dear all, please could you help me to understand this scheme? I do not exactly know what is function of schottky diodes in this circuit.Thanks

author: mertsok
author_rank: Newbie
timestamp: June 07, 2013, 08:40:34 pm
content: Can you provide the full schematic with its application to understand it better. Schottky diode has lower voltage drop, so it can provide higher switching speed and better system efficiency.pcb assembly
Recommended PCBA Houses in Shenzhen - Page 1
Forum section: electronics / general

author: jakeypoo
author_rank: Regular Contributor
timestamp: October 24, 2012, 01:35:48 pm
content: Hey All,I'm going to be having some PCB manufactured and assembled in Shenzhen. Production quantities around 1k-10k units. Pretty usual stuff, 2-4 layers, no BGAs or anything complicated. Some thru, some SMD, wires assembled.There are so many places, and I've had mixed results with some of the places I've dealt with in the past for smaller batches (~100 pcs).Never gone to any Chinese manufacturers before for any large volumes. I was hoping to source some recommendations for board houses in the Shenzhen / Dongguan area that have produced good results for anyone in the past.

author: Koen.Hu
author_rank: Newbie
timestamp: February 23, 2013, 04:16:05 pm
content: We are a leading PCB trading company, we have the reasonable factory can satisfy your meets, if you don't mind cooperating with trading company, Maybe you can send your gerber file and BOM list for price apprasial .regardsKoen,Hu
silkscreen underneath SMT components... - Page 1
Forum section: electronics / general

author: westfw
author_rank: Super Contributor
timestamp: February 10, 2013, 10:13:55 am
content: I'd like to put some identifying silkscreen "underneath" SMT components so that I can easily identify the type of component (assuming, say, otherwise identical 0805 SMT pads) on the completed board. Will this work, or will the thickness of the silkscreen interfere with SMT component placement? (assume for the moment that the symbols will be possible to read; these are relatively large components...)Here's a picture of what I had in mind:

author: jaqie
author_rank: Regular Contributor
timestamp: February 10, 2013, 10:18:41 am
content: if their height may interfere, what about making it a negative instead so that the height isn't unpredictable and uneven? basically a solid silkscreen color for the entire underside of the part, with the text you want missing from that solid color? that could give it a solid platform to sit on instead of a possible teeter totter effect?

author: fcb
author_rank: Super Contributor
timestamp: February 10, 2013, 11:37:46 am
content: Don't do it for passives - you'll risk having misaligned silk on the pads and if they use a thick ink the part may ride up and encourage tombstoning. Your probably OK with the SOIC, although I put a box round the outside.If I'm hand-building small runs of boards I just print out multiple copies of the top silk and colour in the parts, so I end up with flip-book (page for 10K's, page of 100n's, etc...).

author: free_electron
author_rank: Super Contributor
timestamp: February 10, 2013, 05:44:35 pm
content: Down to 0805 no problem. Smaller gives risk of tombstoning.NEVER do this under QFN as it may prevent the pads from wetting during reflow

author: Kremmen
author_rank: Super Contributor
timestamp: February 10, 2013, 09:46:21 pm
content: Yep, doing it all the time and no problems so far. Down to 0805, SOT23 and similar; iron soldering, heat gun, pizza oven - all work with no probs whatever. 0402 and below could be an issue but i don't do that size so wouldn't know.

author: stefanh
author_rank: Contributor
timestamp: February 14, 2013, 12:39:52 am
content: The IPC Compliant Footprint Wizard in Altium automatically puts some silkscreen between the pads following the outline of the component providing a minimum length can be achieved. This works down to 0603 sized components, there is not enough room between the pads of 0402 components for any silkscreen.. I have not had any tomb stoning problems when getting them manufactured.

author: westfw
author_rank: Super Contributor
timestamp: February 14, 2013, 08:39:02 am
content: Thanks everyone!(Man, you work on those PCBs on the big monitor and everything looks swell, and then you print things out "actual size" and realize that they're a lot smaller than you thought!)
Best way to connect pads with the same signal - Page 1
Forum section: electronics / general

author: Twistx77
author_rank: Regular Contributor
timestamp: February 18, 2013, 04:59:12 pm
content: Hi,I'm working in a new PCB and I wanted some advice in which is the best way to connect pads that have the same signal i.e. Ground or power signal in power IC's.Here are three examples. Which of this is the best way to do it? Is there a better one?Thank you.

author: Kremmen
author_rank: Super Contributor
timestamp: February 19, 2013, 07:42:21 am
content: The chip pretty much dictates the way you have to connect. For solderability, you should make the connections cleanly; in that sense the bottom left is a bit messy as pads and traces get mixed.Electrically, supply should be low impedance i.e. wide tracks, use planes, and above all put bypass caps right next to the supply entry pads. The cap should be already visible in the screengrab you attached.The cross connections between adjacent pads probably don't do very much unless the pads draw significantly different currents. On the other hand they won't hurt much either.

author: Twistx77
author_rank: Regular Contributor
timestamp: February 20, 2013, 06:18:36 pm
content: Hi,Thanks for your tips. The bypass caps are not visible because I moved them away to clearly show my point. So by your comment I guess the one in the middle would be the best solution.That's what I expected since the one in the left I only use it when I need to draw substantial current and I will solder by hand.Thank you!

author: David_AVD
author_rank: Super Contributor
timestamp: February 20, 2013, 08:26:44 pm
content: I've moved away from connecting adjacent pads straight across as it makes it harder to visually inspect for shorts after manual soldering.

author: Psi
author_rank: Super Contributor
timestamp: February 20, 2013, 08:59:33 pm
content: Quote from: David_AVD on February 20, 2013, 08:26:44 pm+1 for this.

author: andersendr
author_rank: Regular Contributor
timestamp: February 20, 2013, 09:05:04 pm
content: I agree with David_AVD. I usually will make them look like your middle example so when you are hand soldering, you can see what is happening better.

author: Twistx77
author_rank: Regular Contributor
timestamp: February 20, 2013, 09:29:48 pm
content: Thanks but usually that doesn't bother me since usually I solder right after I finish the design so I usually recognize the power leads of the IC's that are for power stuff.Anyway good adviceThanks!

author: Kremmen
author_rank: Super Contributor
timestamp: February 21, 2013, 04:12:08 pm
content: Quote from: David_AVD on February 20, 2013, 08:26:44 pmA very good point. Didn't come to think of this because i don't usually connect adjacent pads.
Best Gerber DFX ODB++ editor? - Page 1
Forum section: electronics / general

author: geekpcbguy
author_rank: Newbie
timestamp: February 08, 2013, 01:52:06 am
content: Hi I'm looking for opinions and advice about different editors. I have some options in mind, I've been comparing DownStream CAM350, Pentalogix ViewMate PRO and GraphiCode GC-Prevue. Has anyone worked with any of those? Any advice? Thank you

author: marshallh
author_rank: Unknown
timestamp: February 08, 2013, 01:56:05 am
content: I use GC-Prevue and it's sufficient for viewing, haven't tried panelization in it

author: free_electron
author_rank: Super Contributor
timestamp: February 08, 2013, 06:25:59 am
content: If you really need an editor then the best ones are Frontline's Genesis 2000 or Ucamco's Ucam.Those are real gerber / odb editors.Those two tools alone cover 95% of the pcb manufacturers.

author: geekpcbguy
author_rank: Newbie
timestamp: February 09, 2013, 12:25:06 am
content: Thanks for the advice! I'm going to try the trials.. I don't plan to spend so much money on this..

author: jahonen
author_rank: Super Contributor
timestamp: February 09, 2013, 08:19:02 am
content: I have used CAM350 with option 110. It works quite nicely for basic editing, for example, combining different gerber files into one or doing some very basic verification of gerber data against rules. Can't really say if it suits your needs as you don't tell what you are going to do with it.I guess that CAM350 is not so sophisticated than those tools mentioned by free_electron but I it is probably not so expensive either.Regards,Janne

author: free_electron
author_rank: Super Contributor
timestamp: February 09, 2013, 04:05:18 pm
content: Cam350 is a basic tool where you can indeed do some panelisation work , but it ' nowhere near Genesis or Ucam. I know CAM350 also has problems with certain gebrer features ( complex polygons and some arcs ).Ucam has NO problems with gerber. They own the standardUcam is the direct descendant from the Gerber corporation , sold to intergraph , then to Barco thento Mania and now incorporated as UcamCo.Genesis is another 'old name'.Go to any pcb fab and ask them what they run to do their fab processing. It's going to be either Ucam or Genesis (frontline) you can do things like pattern shrinking or expansion to compesate for etching , all kinds og logic operations on layers , converting flashes to strokes and reverse , converting polygons to strokes or meshes to polygons and much much more. Boolean operations between layers / entities.Of course, the question is : do you need that ? A pcb fab does, but a pcb designer doesn't. If it can't be done in the pcb design tool , you probably won't need it as it is fab related. Leave the fab stuff to the fab. You don't have the expertise anyway.

author: Bloch
author_rank: Unknown
timestamp: February 09, 2013, 09:52:18 pm
content: Quote from: geekpcbguy on February 09, 2013, 12:25:06 amAt my first job we used bat files to move / rotate gerber files to make panels.
DesignSpark and SolidWorks Project: Assistance needed ASAP! - Page 1
Forum section: electronics / general

author: lala
author_rank: Newbie
timestamp: February 02, 2013, 09:11:59 pm
content: Hi. I am not sure im posting on the correct forum, but here it is. I have a very time-sensitive project that needs to get done ASAP. Looking for someone to assist. Project is not difficult or complicated, but im not an expert and no time for tutorials. One project is a small simple board design with DesignSpark (its half-way done.) The other is a simple design of some shapes with SolidWorks.Please let me know where i can find assistance or any other useful comments/ideas you might have, id really appreciate. Again, this is needed ASAP!!!Regards.Engineering Student

author: Bored@Work
author_rank: Super Contributor
timestamp: February 02, 2013, 09:16:58 pm
content: So looking for an idiot doing your home work.

author: M. András
author_rank: Super Contributor
timestamp: February 02, 2013, 09:40:57 pm
content: using solidworks is pretty simple intuitive interface and options, you can spend a few hours with trial and error method and in the end you wont have problem with anything, with shapes its easy too, but if its sheet metal its even easier, more predefined modification tools

author: nathancrum
author_rank: Contributor
timestamp: February 08, 2013, 08:29:48 pm
content: Solidworks actually has some fairly good tutorials built right into the help menu. They aren't comprehensive, but they should be sufficient to get started and design a couple simple 'shapes'.