hybridfree/eevblog-posts huggingface dataset:
What to get from MG Chemicals? to make PCBs - Page 1
Forum section: electronics / general

author: Merlysys
author_rank: Regular Contributor
timestamp: September 17, 2015, 01:20:57 am
content: MG Chemicals because its local and a store near me (Sayal) sells their stuff. But the store people are clueless about what they sell. Its the only electronics store near by and they carry plenty of the stock so I rather deal with them.if you have experience with MG Chemicals line of products tell me what to buy to make PCBs. Traces on both sides, components on one side, no multilayer, whats that board called? Forgot as I graduated from EET decades ago, made PCBs in the lab but don't remember the process details.If there is a kit includes everything needed to fabricate the PCBs tell me about that, I rather start with that than with a long list of stuff and forget to get something.

author: microbug
author_rank: Frequent Contributor
timestamp: October 04, 2015, 03:41:02 pm
content: Blueskull is absolutely right, especially about it being better to use a PCB service! Unless you're broke, don't waste your time making your own PCBs.

author: Bud
author_rank: Super Contributor
timestamp: October 04, 2015, 07:04:03 pm
content: I still make my PCBs when i want it quick or when i anticipate the design may change. It is also fun.
Can anyone help me with a Molex camera socket package in Eagle? - Page 1
Forum section: electronics / general

author: jdraughn
author_rank: Regular Contributor
timestamp: August 14, 2015, 01:44:56 pm
content: Hi all, I have never asked for help in the past with Eagle library's. I have always searched on the internet and found tutorials and always been OK, but I am having a heck of a time with creating the package for this camera socket.http://www.digikey.com/product-detail/en/1050281001/WM6827CT-ND/3045224The thing that is throwing me off are the corners and the inside curve. I can create an arc with a radius of 1 like it says in the datasheet, but I am having trouble aligning it to the outside of the corners. It's a little hard to explain exactly. This is by far the hardest package I have had to create in Eagle (but I haven't created THAT many, maybe 20 or so).I can create the Symbol, and the Device from the combined Symbol and Package, I just need some help with the Package part. I am thinking of creating my own breakout board for that $180.00 Flir sensor. I figure it will pay for it self easily in just a few months by allowing me to see where all my heat or cold is going in my house.

author: H.O
author_rank: Frequent Contributor
timestamp: August 15, 2015, 07:28:19 pm
content: Hi,I'm not sure what radius you're talking about or what the problem is with the corners but I had a go at creating the footprint. I donät know if it's up to your expectations but here it is. The datasheet for the socket doesn't say anything about the pin numbering so it's "all over the place", you'll need to renumber them all to your specs.Library contains a single package, nothing else and I just now created it so you really need to double check it!

author: kizzap
author_rank: Unknown
timestamp: August 15, 2015, 10:04:30 pm
content: if you are referencing the external corner rounding, tbh, I wouldn'b bother. draw your outline as a box, because either way the exposed pads are going to be outside that. make sure you add a keepout box as well and all should be good.
Built 20k span ohm meter with ICL7106 - Page 1
Forum section: electronics / general

author: GKM
author_rank: Newbie
timestamp: July 30, 2015, 03:54:43 pm
content: HI, I search for a circuit schematic for built a 20k span ohmmeter with a ICL7106.Does someone have a link?

author: Zero999
author_rank: Super Contributor
timestamp: July 30, 2015, 05:42:35 pm
content: Use your imagination.The ICL7106 is a volt meter IC. A resistance can be converted into a voltage by passing a constant current though it. If you aim for 200mV as the full scale which represents 20k (the decimal place can be adjusted manually) then the desired current can be calculated using Ohm's law.
Gerber issues altium - Page 1
Forum section: electronics / general

author: zisis_A
author_rank: Newbie
timestamp: July 22, 2015, 07:04:53 am
content: I have the following problem when exporting my pcb design as a gerber in altium, the top and bottom layers do not align correctly. the board has 4 mounting holes all three align perfectly when printed but 1 hole seems to be higher in the y axis, this problem gets worse when i mirror the board.
Ordering PCB - Page 1
Forum section: electronics / general

author: Nuno_pt
author_rank: Frequent Contributor
timestamp: July 11, 2015, 11:52:19 am
content: Hi all,Can anyone tell me what is the best place and cheaper to make some PCB in Rogers material?Another question is there any PCB House that accepts the negative of the board to make one?For one I've the Gerber files, but for other I've only the negative of the board, like it was to print and make it homemade.Thanks.NunoCT2IRY

author: IconicPCB
author_rank: Super Contributor
timestamp: July 13, 2015, 06:59:35 am
content: Hello Nuno,In the past we have made some boards in rogers material. Are you looking for multilayer product?Can You provide a sample of the negative image of a board?

author: Nuno_pt
author_rank: Frequent Contributor
timestamp: July 13, 2015, 09:07:12 am
content: Hi,In attach is the files the first one is the negatives that I've, for 1 and for 2 Mosfets.The second one is the gerber files for the 2 mosfet.The third one is the image from the gerber files of the 2 mosfet.Is this helpfull?

author: IconicPCB
author_rank: Super Contributor
timestamp: July 14, 2015, 11:20:39 pm
content: PDF to DXF converter has done its job..poorly.Resulting DXF comes up with some artifacts ( created by polygon intersection) which need to be eliminated .I have imported DXF and can convert it to Gerber without much dificulty. Give me a day or two I ought to be able to present you with preliminary results. Unfortunately there are no dimensions on the PDF so scaling is a problem.Post shortly

author: IconicPCB
author_rank: Super Contributor
timestamp: July 15, 2015, 05:59:01 am
content: Ok,Some developments.Attached converted PDF to DXF M9160X1.DXFOn screen view of imported DXF rawDXF.BMPO screen view of DXF converted to Gerber gerber.bmpand ofcourse the reason for all of this the Gerber file M9160X1.dxf.gbxI can clear up the garbage albeit manually but given the DXF is now available You may want to put in the effort of cleaning up the DXF and I shall be happy to chew it up and spit it out as a gerber.Hope this helps You since the Gerber now opens up the options.

author: IconicPCB
author_rank: Super Contributor
timestamp: July 17, 2015, 09:34:50 pm
content: Any comments Nuno?Do you have the actual dimensioned drawing and the specification laminate thickness?Are you looking for someone to manufacture the board for You?
Creepage, CTI, conductor spacing and the Saturn PCB toolkit - Page 1
Forum section: electronics / general

author: MrLikerBiker
author_rank: Newbie
timestamp: July 14, 2015, 03:16:33 pm
content: Hello, I've been looking into how to ensure conductors are properly spaced on a PCB to withstand HiPot testing.The Saturn PCB kit allows the calculation of conductor spacing for a specified voltage level. This is presumably the creepage distance. However, it doesn't seem to take into consideration the CTI (comparative tracking Index) of the PCB substrate that is used.How can this be?Surely the conductor spacing should vary depending on the CTI value of the substrate used. For example, we currently use a standard FR4 which has a CTI of about 150. However, we could use a substrate that has a CTI of about 600 which should allow closer spacing of the conductors so long as clearance isn't being compromised.Any advice?Thanks.

author: Neilm
author_rank: Super Contributor
timestamp: July 14, 2015, 06:57:29 pm
content: Are you looking for the creepage distance or the clearance distance. The creepage is what is dependent on the CTI, clearance isn't. Hi-Pot testing tests the clearance required for safety, not the creepage. The latter is more for longer term voltage exposure.

author: Smokey
author_rank: Super Contributor
timestamp: July 15, 2015, 04:55:24 am
content: Any of these design specs are going to be based on very specific safety certification requirements. They have very specific product applications, and running configurations/condititons for the product to be certified. The problem is that unless you know exactly who your customer is going to be and exactly what certifications you will need to comply with, it's damn near impossible (and also mostly arbitrary) to try to just throw darts and come up with anything realistic.Most of the calculators and "general tables" are usually based on IPC2221 or IPC9592, but unless you know that is the only thing you need to comply with (and it never is) you will end up mis-specifying your thing and it will never pass when that time comes.I've found unless you want to make a career of being a safety certification expert and work in a cert lab, you should really contract an actual safety certification expert that works in the cert lab you plan on using when you take your product to test. If there is one guy that can tell you exactly what tests you need to pass, it's the guy that will be running those tests.Now if this is just a personal project, then don't worry and just make the creepage and clearance as much as you can. Follow the IPC guidelines if you want but don't sweat the CTI or pollution level or any of that junk. If you are REALLY paranoid, just get a can of conformal coat and spray the crap out of your board when it's done. Problem solved.
Well this is weird... - Page 1
Forum section: electronics / general

author: void_error
author_rank: Frequent Contributor
timestamp: August 16, 2015, 08:16:00 pm
content: http://www.3pcb.com/contact.htmlhttp://www.pcbway.com/contact.htmlWhy would they have two (almost) identical websites?Or one is fake? Even customer reviews are the same.Either way, I'm confused.
Technical Paper Assistance Requested - Page 1
Forum section: electronics / general

author: MCPorche
author_rank: Contributor
timestamp: July 02, 2015, 03:37:51 am
content: Hi Guys,I'm currently attending Louisiana Tech University, purusing a bachelor's degree in Electrical Engineering Technology. I'm working on a technical research paper for my Technical Writing class, and I have to try and come up with solutions to a problem. It was suggested that we pick a problem in our career field or degree program, so I came up with something that I think is a problem in the electronics/electrical engineering community. It relates to construction of PCBs by hobbyists and students.I'm looking for a few people who would be willing to spend a few minutes answering a few questions either via irc, facebook messenger, yahoo messenger, or email. If you build your own circuit boards, and would be willing to help me out, please shoot me a message.Thanks a lot.Monte

author: kizzap
author_rank: Unknown
timestamp: July 02, 2015, 09:45:43 am
content: Hey,Just an FYI, you might get a bit of a response through the #eevblog IRC channel, on afternet.org ;-)

author: MCPorche
author_rank: Contributor
timestamp: July 06, 2015, 02:33:41 am
content: Cool, thanks for the info. I didn't know there was a channel.
PCB Artwork Printing Resolution [OrCAD Layout >> GerbTool >> PDF >> Canon MP280] - Page 1
Forum section: electronics / general

author: onemilimeter
author_rank: Frequent Contributor
timestamp: July 05, 2015, 03:43:59 am
content: Hi...I wish to produce a PCB artwork film positive for UV exposure. The PCB artwork was drafted using OrCAD Layout (v10.3). Then, a PDF version of the PCB artwork was created using GerbTool (v13). Finally, the PCB artwork (in PDF) was printed using Canon MP280. Attached figures show the settings used for converting the PCB artwork to PDF in GerbTool, and the Canon MP280 settings used to print the PCB artwork (in PDF) on paper/film.According to the Canon MP280 specs (http://www.canon.co.uk/printers/inkjet/pixma/pixma_mp280/#p-specification), the printer is able to print at a resolution of (up to) to 4800 x 1200 dpi and with minimum 2-pl ink droplets. My questions are as follows:(a) Will the Canon MP280 (with the settings shown in attachments) print the PCB artwork (in PDF) at the maximum resolution (4800 x 1200 dpi) ?(b) Do we really need an inkjet printer with a printing resolution of 4800 x 1200 dpi or higher to print PCB artwork film positive (or negative) for UV exposure?Kindly advise. Thanks.
Thick black line on schematic - What does it mean - Page 1
Forum section: electronics / general

author: level42jeff
author_rank: Contributor
timestamp: July 14, 2015, 01:28:31 pm
content: I've noticed this on a few schematic drawings, but I'm not sure what it means.See example here:There are 2 thick black lines connecting many points, what does this mean? does it simply mean the ground? And any/all point connecting to it are simply ground?If so, is it normal for there to be 2 ground lines?

author: McBryce
author_rank: Super Contributor
timestamp: July 14, 2015, 01:31:06 pm
content: The thick line is a bus. Think of it like a multicore connection with all those seperate signals (NOT joined together) inside the thick line. It's really just to keep the schematic readable.McBryce.

author: bookaboo
author_rank: Frequent Contributor
timestamp: July 14, 2015, 01:31:26 pm
content: It's a bus, rather than drawing seperate lines for A0-A15 and D0-D7 the thick black line groups them all together. It's purely for neatness.

author: level42jeff
author_rank: Contributor
timestamp: July 14, 2015, 01:34:21 pm
content: Ah, ok. That makes sense.As for the D0-D7 bus, I notice there are 3 points for each, does that mean the connection is literally a Y (When this is to be printed on a PCB) Or am I again overlooking something.

author: Ian.M
author_rank: Super Contributor
timestamp: July 14, 2015, 01:39:09 pm
content: A Y or a daisy chain or some other hookup that connects all points with the same signal name in parallel.Especially on multi-page schematics, busses drawn that way can be a toal P.I.T.A as if only some of the signals in the bus are used on a particular page, unless a list of all the connections for each signal is provided, its very hard to be sure that you haven't missed one of the connections for the signal.

author: McBryce
author_rank: Super Contributor
timestamp: July 14, 2015, 01:40:02 pm
content: I doesn't necessarily have to be a Y in shape, but yes, this means that those three points (for each data line) are to be connected together. In computer systems all devices that need data / address connections are usually all connected in parallel to the data / address buses and the CE / CS (Chip enable / Chip Select) pin of the IC decides which device actually acts on the data.Bryce.

author: langwadt
author_rank: Super Contributor
timestamp: July 14, 2015, 02:10:06 pm
content: and just to add to the confusion you can delete the thick lines the don't do anything,wires with the same name are already connected i.e. every wire with the label D0 is connected

author: level42jeff
author_rank: Contributor
timestamp: July 14, 2015, 02:11:44 pm
content: Thanks for the info guys, I think that clears up quite a bit for me
Presensitized boards method witout transparency - Page 1
Forum section: electronics / general

author: Merlysys
author_rank: Regular Contributor
timestamp: October 06, 2015, 11:51:24 am
content: When using presensitized copper clad boards we create the artwork on a transparency and shine UV light over that transparency so the areas not blocked receive UV light. I wonder if a laser can be used to shine this light instead thus eliminating the transparency process. Laser can scan its beam in a raster pattern like the laser in laser printer.I searched for this but couldn't find anything, if you know about it please give details or post some links.

author: IconicPCB
author_rank: Super Contributor
timestamp: October 08, 2015, 01:27:01 am
content: EdoNork,Got contact details for the poster of the video?

author: sleemanj
author_rank: Super Contributor
timestamp: October 08, 2015, 01:49:08 am
content: Quote from: Merlysys on October 06, 2015, 11:51:24 amEither your UV laser has to be very powerful, or your raster scan has to be very slow, very very slow, very very very very very slow. Also you have the problem of how to achieve your raster in both X and Y directions, one of them is "simple" like the laser printer spinning mirror, the other now you're going to have to transport the PCB along a path or introduce another mirror maybe, and you've now got alignment issues, doing 2 sided would be a mission.... you could make it a cartesian system like a laser cutter or 3d printer of course, but it's still gonna be slow slow slow unless you have a really high power UV laser source.In other words, if you want to make a PCB at home just print a mask, on tracing paper or transparency, and expose to UV all at once.

author: matseng
author_rank: Frequent Contributor
timestamp: October 08, 2015, 03:13:33 am
content: Opposed to the failed attempt in the vido linked by EdoNork this guy actually is successful. And the exposure didn't take to long time either...

author: Sbampato12
author_rank: Regular Contributor
timestamp: October 08, 2015, 03:57:52 am
content: Quote from: matseng on October 08, 2015, 03:13:33 amI've saw this video some years ago. Always tough it is very interesting way to do it.

author: ElektroQuark
author_rank: Unknown
timestamp: October 08, 2015, 09:11:13 am
content: Quote from: IconicPCB onTodayat 02:27:01NO, sorry. Only Youtube page info.
Need advice:Novice in PCB Design - Page 1
Forum section: electronics / general

author: glicos
author_rank: Regular Contributor
timestamp: June 03, 2015, 11:38:29 am
content: Need advice from PCB expert. What is the encircle symbol in the attachment means?Many thanks for input guys...

author: Jeroen3
author_rank: Super Contributor
timestamp: June 03, 2015, 12:33:25 pm
content: 1- Solder jumper2- A snubber?

author: EEVblog
author_rank: Unknown
timestamp: June 03, 2015, 01:14:41 pm
content: Could be a spark gap, or solder jumper pads as Jeroen3 said

author: Jeroen3
author_rank: Super Contributor
timestamp: June 03, 2015, 02:20:13 pm
content: Maybe it becomes obvious with more context?

author: LukeW
author_rank: Frequent Contributor
timestamp: June 08, 2015, 03:53:14 am
content: The second one is a series RC circuit, a snubber component assembled as a single module, designed to go across relay contacts or across an inductive load etc.The first one, as others have said, is likely to be either a solder jumper or a spark gap.
Breadboardkiller is coming back! - Page 1
Forum section: electronics / general

author: kaveendra
author_rank: Contributor
timestamp: May 19, 2015, 11:55:40 pm
content: I was disappointed to see the Aussie companywww.breadboardkiller.com.auhas stopped taking orders. Was also thinking such an operation was not sustainable for the ridiculously low prices (being an Australian business). But got an email from Matthew this morning, saying they will be taking orders in two weeks time.. what a fantastic news to start the morning...

author: kaveendra
author_rank: Contributor
timestamp: May 26, 2015, 12:06:36 am
content: "Boards up to 5x5cm, Get 10 copies for AU$20"Anybody knows a PCB house in Australia, who produce small quantity PCBs with lower price? I have an urgency, and cannot wait till "Breadboardkiller" awakes

author: steve_w
author_rank: Regular Contributor
timestamp: June 15, 2015, 11:50:20 pm
content: Has anybody used these guys?Are the boards made in Australia or China?regardsSteve W

author: cravenhaven
author_rank: Contributor
timestamp: June 17, 2015, 11:23:46 am
content: I just tried to start the process of getting a board made, but they say they aren't accepting new registrations ATM. Check back in a few days they say?

author: breadboardkiller
author_rank: Newbie
timestamp: July 01, 2015, 07:36:02 am
content: Hey All,I'm Matt from Breadboard Killer. I noticed this thread and figured I'd poke my head in and fill you in on what's happening with BBK.First, the website is now live. Registration and ordering are all online. I recently spent an inordinate amount of time rewriting the webpage. I always thought the automated upload thing on OshPark's site was cool so I've coded up something similar for Breadboard Killer. You can now upload design files to the site, it will process the gerbers in the backend (using GerbV) and show you renderings of each layer and the front and back of the PCB.As for your question Steve W, our boards are made in China. I'd love to have them made here but until more people start using the service and I can offset the cost by batching orders together (if people are interested in that) it's not going to be a reality unfortunately.Anyway, if anyone has any other questions about the site please feel free to ask!
ssd1963 pins and visual tft question - Page 1
Forum section: electronics / general

author: Karamel
author_rank: Regular Contributor
timestamp: May 22, 2015, 10:17:39 pm
content: Hi everyone,This is my first topic in here. I am going to design a wav player in this summer. I am therefore researching electronics components and schematics. I think to use ssd1963, stm32f103vet6 microcontroller and some components. However, I didn't understand anything about visual tft pin directions and ssd1963 pins.For example, mikromedia plus stm32 uses ssd1963 and in this schematichttp://www.mikroe.com/downloads/get/1983/mikromedia_plus_stm32_schematics.pdfshows connections but in mikromedia plus stm32 examples definations, there are some pins which are not fitted.unsigned int TFT_DataPort at GPIOE_ODR;sbit TFT_RST at GPIOF_ODR.B14;sbit TFT_RS at GPIOF_ODR.B15;sbit TFT_CS at GPIOF_ODR.B13;sbit TFT_RD at GPIOF_ODR.B12;sbit TFT_WR at GPIOF_ODR.B11;sbit TFT_BLED at GPIOF_ODR.B10; // this is not fitted in shematic? what is the meaning of that?And also, there are some pins, which are not using, in schematic. Such as, TFT-GPIO and TFT-TE. In examples, these pins weren't used by software. These things are a little bit confusing. I want to use minimum pin combination between mcu unit and ssd1963. Can you help me understanding this situation?Best Regars,Karamel

author: Skimask
author_rank: Super Contributor
timestamp: May 22, 2015, 11:47:52 pm
content: Not brain surgery...TFT_xxxx lines go between the STM32 and the SSD1963LCD_xxxx lines go between the SSD1963 and the actual LCD.Those pins are "hidden" from you to make it simple...or maybe not.They're all being used...in the libraries, behind the scenes, etc.I hear there's a helluva demand for underwater basket weavers.

author: Karamel
author_rank: Regular Contributor
timestamp: May 23, 2015, 12:27:59 am
content: Thanks for replying,PF10, which was defined in softwire TFT_BLED, wasn't connected any pin in schematic? but it is using in softwire?

author: Skimask
author_rank: Super Contributor
timestamp: May 23, 2015, 12:57:43 am
content: Here's the address of a really good site to answer all your questions...http://www.mikroe.com/
PCB123 - Page 1
Forum section: electronics / general

author: etechparker
author_rank: Newbie
timestamp: June 03, 2015, 12:45:22 pm
content: Anybody Capturing Designs in Sunstones PCB123? What troubles have you had?

author: rx8pilot
author_rank: Super Contributor
timestamp: June 03, 2015, 03:56:41 pm
content: I used PCB123 in 2009 for a 6 layer board and it worked well. Short learning curve and it got the job done. I showed it to one of my friends and he uses it to this day. Even though I have not laid out a board with it in many years, I have had to interface with it quite a bit since I was doing the mechanics to match the PCB's.The GoodGood for beginners to learn basic PCB layoutShows real-time pricing as you designOne click ordering with no need to prep Gerbers or other process that could bungle things upFREEWell supported, Sunstone is great about helpingThe BadLimited feature setyou can only use Sunstone to make the PCBThe included library is only for reference, MANY parts are wrongFiddly interfaceFor FREE, there is nothing to complain about. I did not want to put any effort into building a library knowing that moving to a commercial package would be important for me. I could see the limitations early on which were not a problem at the time, but they would soon be a problem. It has also been upgraded many times since I last had to deal with it - 2 years ago.I ended up with Eagle which has served me well and now I have my sights set on Altium Designer. PCB123 was a great way to learn the basics.
good textbooks detailing wave soldering and SMD oven soldering (industrial) - Page 1
Forum section: electronics / general

author: SArepairman
author_rank: Frequent Contributor
timestamp: May 11, 2015, 03:13:07 pm
content: I'll post this here too, since its an expert forumI would like to better acquaint myself with the nitty gritty of reflow and wave soldering.What are some good resources for this? I assume I should take a youtube college thermodynamics class first.I can probobly cobble something together by reading a buncha diff resources, but I thought a text made a an author that specializes in the subject might be helpful. This is not for toaster ovens/small scale etc, I am interested for the industrial overview, for medium size production. Also like, tuning the processes and whatnot.I have been asked to provide some oversight and document things at a facility, and I want to be in the know so I can talk shop with them. Or at least not be completely clueless.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: May 12, 2015, 12:52:05 am
content: Quote from: SArepairman on May 11, 2015, 03:13:07 pmGood question. The good old Printed Circuits Handbook maybe?http://www.amazon.com/Printed-Circuits-Handbook-McGraw-Handbooks/dp/0071467343

author: SArepairman
author_rank: Frequent Contributor
timestamp: May 12, 2015, 03:31:18 am
content: sure looks like a good start

author: IconicPCB
author_rank: Super Contributor
timestamp: May 13, 2015, 06:20:42 am
content: Is there particular equipment You will be discussing?

author: SArepairman
author_rank: Frequent Contributor
timestamp: May 21, 2015, 06:09:58 pm
content: Quote from: IconicPCB on May 13, 2015, 06:20:42 amI should know in a few weeks, maybe. I started reading the book linked here and a different one about reflow soldering troubleshooting. It should be enough to get me started.
OrCAD Symbol Libraries - Parts with /SM or /SO or /WHATEVER suffixes? - Page 1
Forum section: electronics / general

author: mbendzick
author_rank: Newbie
timestamp: January 26, 2015, 05:45:27 pm
content: Has anyone learned deep enough info about OrCAD symbol libraries to know what is going on with symbols that have forward-slash endings, such as /SM or /SO or /WHATEVER? These seem to be cousins of their non-slash parts, and copying one seems to copy them all.How would one use those to an advantage? How would one kill off unwanted connections in a library?Process I just did that makes things awkward:I have symbol "HEADER 20X2 WITH MTG PINS". I copied and renamed a new version "HEADER 20X2 WITH AL PINS". These seem to have their genesis with OrCAD's provided libraries, "HEADER 20X2" specifically. But now all of the "HEADER 20X2", "HEADER 20X2 WITH MTG PINS", and "HEADER 20X2 WITH AL PINS" tie back to "HEADER 20X2/SM", so changes to any of those 3 symbols take precedence in changing the /SM part.I'd like to just make "HEADER 20X2 WITH AL PINS" have no relatives.Thanks in advance!

author: nctnico
author_rank: Super Contributor
timestamp: January 27, 2015, 12:22:25 am
content: It would help to tell us which version of Orcad and which program you are using.

author: mbendzick
author_rank: Newbie
timestamp: May 21, 2015, 03:32:50 pm
content: Found out more about this - it applies to at least version 9 through 16.6. They are "Package Aliases". Where a normal symbol has just an icon next to it in the library list that looks like an AND gate, a part with aliases will also have a small hyphen in the AND gate body. This means that it shares the graphical and pin design with other parts, but has unique properties. The intent of this "Feature" was to allow you to make a 7400 in a DIP, a 7400 in an SOIC, and a 7400 in a TSSOP, all using the same symbol, but with different orderable part number and footprint name attributes pre-assigned in the symbol.
Orcad File Conversion.. Need somebody to convert. - Page 1
Forum section: electronics / general

author: mrpackethead
author_rank: Super Contributor
timestamp: May 19, 2015, 08:20:45 pm
content: Hi,is anyone out there able to convert an orcad file for me, and convert to a pdf? Happy to flick someone a few $ by paypal if they can.

author: mrpackethead
author_rank: Super Contributor
timestamp: May 19, 2015, 11:50:15 pm
content: Resolved.... Thanks.
Limor Fried interviews Paul Horowitz - Page 1
Forum section: electronics / general

author: Excavatoree
author_rank: Frequent Contributor
timestamp: May 30, 2015, 03:36:17 pm
content: I did try to search, but please delete if this is a duplicate thread. I thought some may be interested.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 30, 2015, 05:58:08 pm
content: https://www.eevblog.com/forum/chat/ladyada-interview-with-paul-horowitz-the-art-of-electronics/?topicseen

author: miguelvp
author_rank: Super Contributor
timestamp: May 30, 2015, 06:20:57 pm
content: Actually Excavatoree posted it first but I guess it makes more sense to be on General Chat than in here.

author: Excavatoree
author_rank: Frequent Contributor
timestamp: May 30, 2015, 06:43:49 pm
content: Quote from: miguelvp on May 30, 2015, 06:20:57 pmI intended to put it in general chat. I apologize.
collaboration for new product PCB design. - Page 1
Forum section: electronics / general

author: technomastermind
author_rank: Newbie
timestamp: April 23, 2015, 03:29:57 am
content: hey guysi am looking for collaboration with designing the printed circuit boards for my project.the components have been chosen and the PCB footprints established.all that remains are the actual schematic layout and placement of components on the PCBs.my PCBs are an irregular shape due to the design of my product,please refer to photos.there are no exotic components all parts are of off the shelf variety.I do have a good understanding of electronics but have never actually got around to designing my own PCB,please forgive me if ive posted in the wrong location,and move post if necessary.kindest regards

author: ludzinc
author_rank: Unknown
timestamp: April 23, 2015, 03:54:36 am
content: 1. Where are you?2. Collaboration means "pcb layout for free" for you're paying by the hour?3. Complexity?4. What tool?5. Any care and no responsibility?

author: technomastermind
author_rank: Newbie
timestamp: April 23, 2015, 08:07:16 pm
content: HiThanks for your reply ludzinc.i am living in the united kingdom,the complexity of the PCBs are fairly simple.Of the two PCBs i need designing one is to provide power and 2.4ghertz remote control,and the other to provide an internal USB hub and step down voltage regulator.There are also a number of input and output connectors to provide internal and external connections.please excuse my ignorance with regards to the rest of your reply i do realize that people cant be expected to do things for free.what would be the going rate to get PCBs designed for manufacturing?i have searched for the schematics for the z2k2dc - zr4 remote control relay board and i intend to use a kim-055l step down voltage regulator as its compact size and meets my needs nicely.Also i would need a plug and play USB controller chip to power 4x USB ports that would work with linux,android,windows.if i could actually find the schematics then i should be able to drag and drop them into my design sheet thus designing my own PCBs.I have spent a great many hours designing and redesigning my physical product to prototype stage and every step of the way having to learn how to work with a new set of tools.Time is always up against me and i am passionate to get my product to market,so anything that could speed up this process would be fantastic.kindest regards

author: 8086
author_rank: Super Contributor
timestamp: April 23, 2015, 08:22:33 pm
content: I have sent you a PM.
Thicker than 1.6mm PCB Stack-up - Page 1
Forum section: electronics / general

author: guscrown
author_rank: Regular Contributor
timestamp: April 22, 2015, 08:39:22 pm
content: Most (or most likely all) of my PCB stack-ups are 1.6mm (62 mils), but I am now in the need of doing a thicker PCB due to mechanical reasons (we need a thicker board so the customer doesn't break it easily when pressing on buttons).I was thinking of going up to 2mm (78 mils), but I'm not sure if I should just increase the dielectric thickness in the middle of the board?My board:Layers: 4 (L1 = signal, L2 = ground plane, L3: power plane and some signals, L4: pads for buttons).I have a pair of differential signals on L1 that I need to control their impedance to 90ohms, this is my original thinking:Top Solder: 0.4milsL1 - Copper: 1.4 milsDielectric 1: 6.7 milsL2 - GND plane: 0.7 milsDielectic 2: 60.3 milsL3 - Signal and VCC: 0.7 milsDielectric 3: 6.7 milsL4 - Copper: 1.4 milsBottom Solder: 0.4 milsTotal: 78.7 mils or 2mmI just simply added the extra thickness to the center of the board, but I'm not sure if that is the ideal solution. All feedback is appreciated.

author: tggzzz
author_rank: Super Contributor
timestamp: April 22, 2015, 10:58:49 pm
content: How certain are you that 2mm is sufficient where 1.6mm isn't? My gut feeling is that if someone is breaking boards by pressing buttons, then 25% thicker isn't guaranteed to solve the problem.19" racks of military equipment traditionally had the bottom 6U left empty - because that was the part the squaddies kicked in frustration!

author: guscrown
author_rank: Regular Contributor
timestamp: April 23, 2015, 01:17:34 am
content: I can't be 100% certain, to be honest. Other than what the mechanical engineer required. I added additional mounting holes for additional support but they still want the board to be thicker.I've seen PCBs go up to 1.8mm, but I don't really know where the extra stuffing goes, I am simply assuming that it goes in the core of the PCB

author: SeanB
author_rank: Super Contributor
timestamp: April 23, 2015, 06:14:46 pm
content: Go for a 6 layer board, with the front and back being the added layers. Make the front a ground plane with large clearances around the switches and connectors, and the back layer the same. The copper will provide extra bracing against tension on the rear and at the front, which will make the whole board stiffer and also thicker. That will get you over the 2mm mark, and you can simply use vias to bond all the ground planes together, including the one inside, and the controlled impedance traces will benefit from the 2 layer ground plane both sides as well.As well leave a row clear on the top and bottom of the switch rows that is about the spacing of the switches, and place a via there by each switch that has clearance in all layers of about 5mm, so that if needed you can drill it out and place a support brace direct by the switches without needing a board respin, just a simple extra drill operation.
component swap - Page 1
Forum section: electronics / general

author: obiwanjacobi
author_rank: Super Contributor
timestamp: May 03, 2015, 01:04:47 pm
content: I was just thinking - when laying out a board with a couple of LEDs with series resistors, if you could say that when a passive component is in series with another passive component you could swap them without any change to the electric properties of that circuit.Is that true?And if so, are there any CAD programs that allow that (I was in KiCad and that doesn't even have gate swapping - great disappointment)...?Thoughts?

author: IconicPCB
author_rank: Super Contributor
timestamp: May 03, 2015, 10:34:02 pm
content: If laying out according to a netlist.. source of netlist needs to be changed , netlist refreshed and then artwork generated.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 04, 2015, 12:51:48 am
content: Yeah, you would have to have a "branchlist" instead -- provides freedom of series connections instead of parallel. (A netlist provides freedom of parallel connections, instead of series.)The netlist is most common because of our bias towards constant-voltage (branches in parallel) circuits and topologies, which ultimately is underlaid by asymmetries of physics (volts beget energy levels which are fixed by quantum effects; current begets only energy *rates*).Strictly speaking, I suppose a more precise netlist would call out both branches and nodes. PCB tools usually autogenerate this from placement (i.e., the ratsnest). Some tools, I think, would be able to support that (e.g., Altium's From-Tos).Conversely, a less precise, and much less useful, netlist would call out neither branches nor nodes...Tim

author: xygor
author_rank: Regular Contributor
timestamp: May 07, 2015, 06:26:27 pm
content: You might not want to swap if e.g one of the component leads is connected to its case.
manufacturer credebility - Page 1
Forum section: electronics / general

author: zerorisers
author_rank: Regular Contributor
timestamp: March 28, 2015, 03:05:25 pm
content: Hello everybody, I found a local manufacturer here in the states. I was wondering if anybody here has ever used this company, and if so what are your experiences with them.http://www.ptiassembly.com/

author: Christopher
author_rank: Frequent Contributor
timestamp: April 01, 2015, 07:00:53 pm
content: Look like a "real" business rather than Seeedstudio etc.Most likely they won't bother assembling your 10 5x5cm boards...

author: zerorisers
author_rank: Regular Contributor
timestamp: April 02, 2015, 11:41:48 am
content: Quote from: Christopher on April 01, 2015, 07:00:53 pmI took a tour of their company earlier this week. If they make boards for TI; I guess they are decent.

author: Quark-elec
author_rank: Contributor
timestamp: April 16, 2015, 12:44:00 pm
content: give a trial to try
PC for Sentaurus TCAD simulations - Page 1
Forum section: electronics / general

author: Allse
author_rank: Newbie
timestamp: April 12, 2015, 06:47:17 am
content: Hello everyone,I need some advice on a very specific PC build. I am working with semiconductor device simulation using technology CAD from Synopsys. I was asked to build a new PC dedicated for these simulations and I have limited budget of 1500$(US) (not including monitor and peripherals). This system is not meant for graphics rendering but rather doing mathematical computation. It will run the software via VMware using RHEL 6.Please suggest which components would result in shortest simulation times as I would like to have the best balanced system.Thanks.

author: IconicPCB
author_rank: Super Contributor
timestamp: April 13, 2015, 03:00:37 am
content: Accost the author of software.Does the software benefit from multiple cores?If not which single core processor will give You best performance?Get an estimate of number of data points in Your simulation and how much memory each data point will require ( minimise need for swap space access ). Get as much RAM as is specified by the author and then some more.Other option a low latency motherboard that is a motherboard intended to be used in server applications rather than eye candy application.
Finding 3D Models (at Samtec) - Page 1
Forum section: electronics / general

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 08, 2015, 07:39:09 pm
content: Bothered with finding 3D (.STEP) models? This may help:- If you have a Samtec catalog handy, it's a lot easier. Their website is dreadfully slow and painful to browse. Sorry about that...- Their 3D models are available from their FTP,ftp://ftp.samtec.com/customermodels/BasicModels/STEP/but don't go there, it's a massive index (over a meg!) and takes forever to load, every time.So, save the index as text, and find the file you're looking for offline.I suggest looking through the catalog for something of interest (e.g., TSW headers), then searching on a partial part number (e.g., TSW-108 = TSW series, 08 pins per row), and checking in that range if your desired part (or similar) is listed. The models are generic (e.g., plating is always -X-) so you can't simply enter a part number straightaway, and guessing the complete filename is unlikely.- Yes this is specific for Samtec, but a lot of the parts they make are compatible, or industry standards (like headers and junk). So even if you're buying, like, a Harwin or Assmann (snicker) part that doesn't have a 3D model (or may, but you have to trudge through the manufacturer's website to find it), you might find something close enough, even if you aren't buying Samtec.Tim
How to connect to power plane - Page 1
Forum section: electronics / general

author: pcblearner
author_rank: Contributor
timestamp: April 21, 2015, 12:35:14 pm
content: HelloI have a project where I power a lot of LEDs - about 10A (50W) worth. I am making a 4 layer PCB with a power plane. A DC power socket is mounted through-hole on the PCB. That connects to a power switch. I want the output of this power switch to connect to the power plane. What's the best way to do this?Obviously my first thought is a via, but I don't know how big it needs to be to handle the current. The calculators on the net (like Saturn) use terms I don't understand like: "Via Hole Diameter" (Is that the drill hole diameter or the total via diameter?) and "Ref Plane Opening Diameter" (??).Also, if the required via ends up have a really large diameter, is there a preferred way to use closely spaced smaller vias connected together by track?I guess at the end of the day, I'm just trying to figure out the safest via size for distributing 10A through to the internal power plane.Thanks for your help in advance.

author: tszaboo
author_rank: Super Contributor
timestamp: April 21, 2015, 12:52:42 pm
content: What? 4 layer boards for LEDs?Just order the boards with thicker copper if you are afraid of the voltage drop, which you should not be, these are LEDs, and they have a series resistor or a current source running them.Use multiple vias if you have to. 10A easily goes through 7-15 0.5mm via like they are not even there. It is not like the PCB really going to cost more for more vias (at least not for people who make <1000 boards).

author: pcblearner
author_rank: Contributor
timestamp: April 21, 2015, 01:18:03 pm
content: Quote from: NANDBlog on April 21, 2015, 12:52:42 pmThere are other ICs as well, and I thought it was a good idea to go 4 layer to have a solid ground plane for EMC minimisation..QuoteThanks. I think I had confused myself. I was worried about via current ratings.. but when the via is directly part of the power plane itself, current ratings aren't such a problem anymore!!
Can this be simulated in Altium? - Page 1
Forum section: electronics / general

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: April 04, 2015, 08:33:50 am
content: I have to admit I am somewhat a fun of circuit simulation. I use PSpice and most of my simulations usually not that complex - 10-20 passive components, one or two opamps. I also hate PSpice because of how ugly broken and unfriendly schematic editing tool that comes with it - "OrCad Capture".Here I have attached a single schematics for Transimpedance amplifier. There is a single CURRENT pulse source that is used to simulate a photo diode. I got this simulated in PSpice in about 30 minutes including import of OPA659 model that I downloaded from TI website. Can this be simulated in Altium? Today I have heard a huge rant from somebody who spent 3 days trying to tweak SPICE simulator in Altium to converge with exactly same configuration. Conclusion - current sources in Altium and current pulse (IPULSE) do not work.Is it true? Can anyone share their experience with subject?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 04, 2015, 06:15:50 pm
content: I've found it's exactly as easy and troublesome as any other commercial grade simulator.All of them, from free 3f5 SPICE, to $10k+ Altium's SPICE engine, are all based on either the original Berkeley 3f5, or the somewhat later XSPICE (also an academic byproduct; Georgia Tech I think??).They almost all have custom tweaks, like PSpice's proprietary notation (syntax, built-in functions, and probably convergence tweaks), Altium's partial support of many things (including some PSpice, and maybe just a hint of HSpice), and probably most significantly, LTSpice's heavily tweaked solver ("modified TRAP", actual real no fooling multiprocessor support, etc.).In short, it doesn't matter what you're paying (or not), they all suck uniformly, just in different ways...Anyway, not to continue into the relative differences of the various packages, I'll simply close in saying: no, there's nothing fundamentally different about Altium's. It's harder to drive, but the convergence is just as good/bad as the user sitting in front of it.Tim
Altium Vault - any good? Worth it or not? - Page 1
Forum section: electronics / general

author: pugglewuggle
author_rank: Contributor
timestamp: March 31, 2015, 10:28:25 pm
content: I like the idea of having re-usable circuits that you can "plug in" to to different projects. I'd like to be able to share these between users if possible.Does anyone have any experience with Altium Vault server? Is it any good? How much did you pay for it? Is it worth it? Go!
LTSpice - creating a custom model - VDCS - Page 1
Forum section: electronics / general

author: daqq
author_rank: Super Contributor
timestamp: May 21, 2015, 11:36:20 am
content: Hi guys,I need a part put into a simulation in LTSpice. I've got the voltage vs current characteristic, it's very nonlinear, with ups and downs. Ideally I'd enter a table with known points and interpolate between them.I found the Voltage Dependent Current Source part, which seems ideal, expecially in the lookup table mode. But I can't find any examples on its use, entering it or anything else. Could anyone please provide me with an example of a Voltage Dependent Current Source being used for such a purpose in the LTSpice format?Gxxx n+ n- nc+ nc- table=(<value pair>, <value pair>, ...)Or anything else would be very helpful.Thank you,David

author: IconicPCB
author_rank: Super Contributor
timestamp: May 22, 2015, 02:25:14 am
content: Hello Daqq,I recommend to You LT Spice yahoo groups.Very knowledgeable mob. Plenty of examples and plenty of helpful people.https://groups.yahoo.com/neo/groups/LTspice/info

author: daqq
author_rank: Super Contributor
timestamp: May 22, 2015, 07:09:44 am
content: Thanks, found my answer there.For others:To create a lookup VDCS place your part, then in its properties table enter the line Value to be in the following format:Code:table( -1, 3, 0, 2, 1,-1)This would be a part where you know that @ -1V across the input terminals of the source you have 3 Amps, @0V 2 Amps and at 1V you get -1 Amps.
Need help Testers for Eagle to KiCad ULP scripts - Page 1
Forum section: electronics / general

author: lachlanA
author_rank: Contributor
timestamp: March 29, 2015, 12:11:18 pm
content: Hi, I have a number of Eagle ULP's which convert Eagle 6.xx SCH to KiCad SCH lib/mod's.It's Alpha stage at the moment, and I have only testing it on Linux.So need's some one who has windows version of Eagle version 6 to test it.It's hosted on GitHub.https://github.com/lachlanA/eagle-to-kicadLachlan