hybridfree/eevblog-posts huggingface dataset:
plasma cleaning PCB ? - Page 1
Forum section: electronics / general

author: coppercone2
author_rank: Super Contributor
timestamp: December 01, 2018, 03:16:03 am
content: Why is this done? Can you improve the solder joint quality, or is it just for the silkscreen ?

author: Smallsmt
author_rank: Frequent Contributor
timestamp: December 01, 2018, 09:07:01 pm
content: You remove oil and silicones and for a short time the surface activation increase adhesion.

author: coppercone2
author_rank: Super Contributor
timestamp: December 02, 2018, 01:12:14 am
content: yes but does it have any effect on soldering (the flux is dirty anyway)?

author: Harjit
author_rank: Regular Contributor
timestamp: December 09, 2018, 01:26:36 am
content: We plasma cleaned assembled boards before they were conformal coated so that the conformal coating adhered better and there weren't any residuals which would result in dendrites.

author: coppercone2
author_rank: Super Contributor
timestamp: December 09, 2018, 01:40:33 am
content: can you elaborate on that? I don't understand why it would have any effect on dendrites (i thought it was a solder strain related process)?

author: Slow Poke
author_rank: Contributor
timestamp: December 09, 2018, 10:00:21 pm
content: Quote from: coppercone2 on December 02, 2018, 01:12:14 amWell, sure....read this:https://plasmatreatment.co.uk/wp-content/uploads/2016/09/Henniker-Plasma-Technology-Overview.pdf
Prometheus / Zippy Robotics - Page 1
Forum section: electronics / general

author: Slow Poke
author_rank: Contributor
timestamp: November 23, 2018, 06:49:07 pm
content: Soooooo what's become of the Prometheus PCB Mill?https://www.zippyrobotics.com/Since 2015.Not shipping yet?.Or maybe you have one. Review, please. Pretty please! Looks good on-screen.....

author: Slow Poke
author_rank: Contributor
timestamp: November 25, 2018, 08:29:25 pm
content: This may have eclipsed Prometheus:https://cirqoid.com/Than again, Latvia, far from California.

author: Slow Poke
author_rank: Contributor
timestamp: November 26, 2018, 04:51:22 pm
content: Came across this from about 19 months ago - check reply #8:https://www.eevblog.com/forum/reviews/is-othermill-worth-it/Zippy web site's still up but no response from inquiry made there. Still offering to take pre-orders.Is this real?

author: ar__systems
author_rank: Frequent Contributor
timestamp: November 26, 2018, 05:46:42 pm
content: Take a guess

author: Slow Poke
author_rank: Contributor
timestamp: November 26, 2018, 06:15:46 pm
content: Quote from: ar__systems on November 26, 2018, 05:46:42 pmLooking at Bantam Tools' Othermill - they're nearby in Berkeley, CA, not far from the Gilman Grill: tasty Chorizo & eggs....worth my time to visit Bantam after breakfast maybe....?https://www.bantamtools.com/

author: Slow Poke
author_rank: Contributor
timestamp: November 27, 2018, 03:09:29 am
content: Quote from: ar__systems on November 26, 2018, 05:46:42 pmK, whoa. Response from Rocco @ Zippy Robotics ~half hr ago:"Getting close. I'm expecting to begin shipping the pre-orders in January and finish in February if there aren't any other obstacles or delays."As Zippy/Rocco's waaaay out on Long Island - St. James, New York - I won't be visiting soon. Anyone here from there?

author: Slow Poke
author_rank: Contributor
timestamp: November 27, 2018, 11:58:50 pm
content: Stopped by Bantam Tools  today - employees inside but door locked to public; a very Berkeley kinda crew let me in. Largish room in the rear was production/repair, office & conference room in front, all modern, clean, and very much a going concern. Bantam's web site pics taken there.Atmosphere has the stink of the Yuppie,justmy kind of place. They asked me to email for date/time look-see; I did, asking to bring a few files for an Othermill demo.We'll see!

author: Slow Poke
author_rank: Contributor
timestamp: December 05, 2018, 02:09:04 am
content: Quote from: Slow Poke on November 27, 2018, 11:58:50 pmThe instant I asked for a demo using my gerbers, the fire died. Until can do, so has my interest in Bantam Tools.So. Back to Zippy/Prometheus, in perpetual development and on hold....my gerbers go to online vendors....
Flux-Free Solder for SMD Soldering? - Page 1
Forum section: electronics / general

author: arbe
author_rank: Newbie
timestamp: December 01, 2018, 04:04:35 am
content: When soldering surface mount components using a gull-wing tip, a flux pen, and the drag soldering technique, wouldn't it be better to use flux-free solder? It seems that the rosin/flux is going to burn away anyway when it gets applied to the gull-wing tip, so what's the point of generating those additional fumes? That said, I can't seem to find many options for flux-free solder, and it seems to mostly be designed for jewelry, not electronics.

author: Bassman59
author_rank: Super Contributor
timestamp: December 02, 2018, 07:20:40 pm
content: Quote from: arbe on December 01, 2018, 04:04:35 amThe flux cleans the connections, ensuring a better solder joint.

author: Berni
author_rank: Super Contributor
timestamp: December 02, 2018, 07:27:27 pm
content: It does still do a bit of its job on the tip. Ever notice how after a while the solder blob on the tip of the iron starts to act different, it loves to form these spikes and looks dull and such. As soon as you add fresh solder it forms a nice smooth sphere again. The flux keeps the ball of solder on your tip oxide free so it behaves nicer.Its not like it produces that much fumes (Or you have a particularity nasty solder flux in yours), can easily be dealt with just a light breeze to blow it away.
PCA Assembly - POE PCA - Page 1
Forum section: electronics / general

author: drauzinho
author_rank: Newbie
timestamp: December 01, 2018, 02:40:25 am
content: Hi, does anyone knows about this company ?http://www.poe-pcba.com/Quoted some boards and assembly with them and the price was really good, better than AllPcb, which is very cheap for PCBA, but I didn't find anyone that used them for prototypes.Cheers.

author: ataradov
author_rank: Super Contributor
timestamp: December 01, 2018, 03:03:18 am
content: I suspect this is spam. But I still went and checked it out. It is bad, the site is very slow to load and feels sluggish. No actual ordering/quoting form to be seen.If you are going to spam, at least spam the good stuff.

author: drauzinho
author_rank: Newbie
timestamp: December 01, 2018, 03:18:31 am
content: Do you have any good/cheap PCBA recommendation ? I'm willing to go with Allpcb. Thanks.

author: ataradov
author_rank: Super Contributor
timestamp: December 01, 2018, 03:22:55 am
content: If you are real and indeed got a quote that was cheaper than AllPcb, you may just try them and see what happens. It is possible that nobody uses them because they did not make nay effort to advertise.It is hard to tell without knowing your volumes, complexity of the board, etc.I have not tried, but I heard that AllPcb works fine for moderately complex boards. But so are many others. In this market you are likely to have a good experience rather than a bad one with any known company.
Test Jig for 3.5mm jack sockets? - Page 1
Forum section: electronics / general

author: ubbut
author_rank: Regular Contributor
timestamp: November 20, 2018, 09:58:12 am
content: Hi,I am looking into building a test jig for a product which uses 8x 3.5mm jack sockets. All of these need to be tested.I can not just use pogo pins to connect to the board, because I want to make sure the sockets themselves are soldered correctly and the product is actually working as intended.My first iteration of such a test jig was just mounting 8 jacks to a panel. It kind of works, but the insertion force of 8 jacks at once is somewhat too high.I am wondering if there are special tools for this kind of testing. Or maybe 3.5mm jacks that are a tiny bit smaller, so they easily slide in and out?Of course the obvious solution is to plug in 8 cables one by one, but I am looking for a simpler solution that I can also scale up to more sockets.thanks a lot

author: 1276-2449-1-ND
author_rank: Regular Contributor
timestamp: November 30, 2018, 01:58:28 pm
content: I'm trying to figure out something similar, but in the meantime am using individual colour-coded cables.The two big problems I ran into are: 1. Insertion force for multiple jacks all at once is quite high and I'm worried about damaging the PCB. 2. Controls are largely obscured by the jack jig. They can't be tested from the back because the jack switch is used in almost everything.

author: Nauris
author_rank: Regular Contributor
timestamp: November 30, 2018, 05:43:30 pm
content: Quote from: ubbut on November 20, 2018, 09:58:12 amIf I were building such test jig, I would use small pneumatic cylinders to push them in one or two at once in sequence.
Can i use drag feeder in Chmt530p4 pick and place? - Page 1
Forum section: electronics / general

author: istipb
author_rank: Newbie
timestamp: November 27, 2018, 11:41:53 am
content: Hi i am following this pick and place discussion for sometime. I want to take the charmhigh chmt530p4 or chmt528p pick and place machine. But i dont want to invest that much money on pneumatic feeders at the beginning. So can i use drag feeder instead of pneumatic feeders?Thanks.

author: overthere
author_rank: Newbie
timestamp: November 29, 2018, 03:30:42 pm
content: I have the CHMT560p4, and i really recommend to buy propper feeders.That money is well invested, as you want to avoid any failure issue upfront, otherwise you have to do too much manual fixing in the end.And then, you can do hand assembly, if you have to fix too much.

author: istipb
author_rank: Newbie
timestamp: November 30, 2018, 02:10:34 am
content: Thanks for your reply. Are you using original Yamaha feeders or from Charmhigh?

author: mrpackethead
author_rank: Super Contributor
timestamp: November 30, 2018, 06:42:45 am
content: You'll get good yamaha clones from around $US60 from ksunsmt ( ksunsmt.com ). I've bought lots of them from them, and they are really good value, some of them have now done 100's of reels and are still going fine.if the machine is designed for using pneumatic feeders then i imagine you'd have problems using drag feeders..
Just got a T962C reflow oven - Page 1
Forum section: electronics / general

author: PartialDischarge
author_rank: Super Contributor
timestamp: November 29, 2018, 09:16:54 am
content: Yesterday it did arrive. Its big with 6 lamps covering side to side, and two temp sensors hanging inside there. From what I've read this is not like the T962 where some areas turn unsoldered.Comes with 8 profiles and gives hints as to which is better for what solder. Just tried one program and it did follow the profile quite well.Haven't tested it with boards yet, but did two important mods: changed a small 12V fan in the control panel, high pitched noise was horrible, and added a 100ohm resistor to the new one, these small ones spin too quick. Also added some tape to the hole of the buzzer inside, again too loud.
Anisotropic conductive film (ACF) bonding technology - the future of soldering? - Page 1
Forum section: electronics / general

author: alanambrose
author_rank: Frequent Contributor
timestamp: November 23, 2018, 05:09:55 pm
content: not sure exactly which section to put this in:http://www.eenewsautomotive.com/news/bonding-replaces-soldering-automotive-environmentsAlan

author: tsman
author_rank: Frequent Contributor
timestamp: November 23, 2018, 05:36:56 pm
content: Similar tech has been around for years now. You can buy 3M 9703 "Z tape" which does the same trick but without the expensive & complicated system they mention in the article. Expensive stuff though. It works by embedding lots of separate metal particles into the tape which aren't in contact with each other.
PnP files from Eagle CAD ready for production ? - Page 1
Forum section: electronics / general

author: baremetal
author_rank: Newbie
timestamp: November 24, 2018, 09:47:30 am
content: Hello all,I have experience with preparing files for PCB production. (Generating Gerber and Drill files). Now, I have board that I need to have assembled by the manufacturing company and I don't know what type of files I need to send.So I know that I have to send BOM and production files, and also Pick and place files. I found that I can generate PnP files in Eagle with mountsmd.ulp script but I don't know if that format is going to work for manufacturer. Also, I had some custom footprints created on this board, and I want to know how this affects the PnP files.Thanks,

author: Jeroen3
author_rank: Super Contributor
timestamp: November 24, 2018, 12:22:18 pm
content: I don't believe there is a standard format for pnp files. I also havevisualplaceulps, which export csv files.Sometimes I just provide the board file, depends on the sensitivity of the project.

author: jmelson
author_rank: Super Contributor
timestamp: November 24, 2018, 04:46:55 pm
content: Quote from: baremetal on November 24, 2018, 09:47:30 amWell, does Eagle provide any sort of placement file? What they want is a file with type of component, X-Y position of center of component, rotation of component, and maybe part identifier. So, it could look like :C46 10.43 13.65 90.0 0.1UFAnd so on. (Above units would be mm.)I would expect if the CAD package can generate such a file, they will already have a script or program that will convert it automatically from most common CAD systems.Jon

author: Jeroen3
author_rank: Super Contributor
timestamp: November 24, 2018, 08:25:21 pm
content: That is what the mountsmd generates. It might not be in the correct format, but the data is there. Nothing excel can't fix.QuoteOtherwise, edit the ulp yourself.

author: baremetal
author_rank: Newbie
timestamp: November 25, 2018, 03:37:43 pm
content: Thanks,I will try with mountsmd, and I will see if that works for my manufacturer.
D-sub connector trays for p'n'p - Page 1
Forum section: electronics / general

author: eeviking
author_rank: Regular Contributor
timestamp: November 21, 2018, 09:57:12 am
content: Do anyone have experience with trays for pin in paste D-sub connectors?I need to find or CNC some trays for 9, 15, 25 and 50pin straight connectors but can't even find good pictures of any.

author: ebclr
author_rank: Super Contributor
timestamp: November 21, 2018, 10:51:41 am
content: This may helphttps://www.norcomp.net/3d-models
A way to get small volumes of a reenterable flexible potting compound - Page 1
Forum section: electronics / general

author: SeanB
author_rank: Super Contributor
timestamp: November 13, 2018, 05:30:11 pm
content: Video from John Ward, showing a waterproofing mix for electrical connections.Looks like a very good way to get a flexible potting material, that will provide both environmental protection, flexibility and also is reworkable as well to some extent, plus is available off the shelf ( in the UK at least, as that is where JW is located) in small volumes.https://amzn.to/2Dy8SZRis his link for it.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 15, 2018, 07:06:00 am
content: Rapid and Farnell also stock it.Works quite well.but I find it didn't set quite as stiff as I'd like, and is pretty messy to get off if you need to.It's silicone based so everything in the vicinity will get slippery, and afaik no solvent will clean it up easily,l.
Reason for the capacitor failure? - Page 1
Forum section: electronics / general

author: ar__systems
author_rank: Frequent Contributor
timestamp: November 13, 2018, 11:45:49 pm
content: I'm investigating capacitor failure in the production board. The cap is 1210 35V 4.7uF. I'm waiting for the part number from the assembler. Obviously I researched the issue already; and I've dealt with stressed cracked caps in the past, but this is something else. First of all, this cap is in the center of the board and the nearest mounting hole is 2 inches away. Also, the failure does not look similar to typical stress cracked caps. In fact they don't look like any other failed cap.The cap was sitting between 24V line and ground, so pretty much it sees only DC. There were 5 more on the same bus they all are fine. The board was tested at production and I believe they run them for 1 hr during QC. It worked for some time in the field, and then failed.Upon investigating the board the failed cap was identified. It was presenting itself as a 15.0 Ohm resistor. The failure originated in the cap: after it was removed from the circuit it worked fine.So... I'm looking for some advice -- whether it is random manufacturing defect, or something else. Attached is a picture of the cap from a side. As you can see it is split perfectly.The assembler was scrambling to get any caps, maybe they got some bad stuff...Appreciate any help.

author: chris_leyson
author_rank: Super Contributor
timestamp: November 14, 2018, 01:14:26 am
content: That's one of the big problems with MLCCs higher capacitance means thinner layers and a lot more manufacturing steps. The more layers you put in then the probability of an axial fracture increases. In a high volume commericial product you would see leaded electrolytic caps used in that application reliability being the simple reason. Hopefully it's a one off defect in your case.

author: wraper
author_rank: Unknown
timestamp: November 14, 2018, 01:23:58 am
content: That line running along the cap looks like severe layer delamination. I'd assume it was defective from the beginning.

author: Niklas
author_rank: Frequent Contributor
timestamp: November 14, 2018, 08:25:49 pm
content: Could it be related to the temperature profile during the soldering process? A larger package would most likely need a slightly slower temperature slope for both heating up and cooling down.
Ultrasonic cleaning and xtal ? - Page 1
Forum section: electronics / general

author: cgroen
author_rank: Unknown
timestamp: November 13, 2018, 10:43:15 am
content: I have a ultrasonic cleaner/bath and using Chemtronics fluid. I have heard some comments that cleaning with ultrasonic can have a negative impact on crystals and such?Any experience regarding this ?

author: sstepane
author_rank: Regular Contributor
timestamp: November 13, 2018, 11:31:13 am
content: Hi,Have been cleaning boards with xtal (12mhz, rtc xtals) - seen no issues. There's a rumor that the xtal could be damaged if its frequency is close/same as ultrasonic cleaner (20-42kHz), but not sure about it and, afterwards, where do you find such an xtal?

author: Gribo
author_rank: Frequent Contributor
timestamp: November 13, 2018, 04:20:45 pm
content: Low power watch crystals are in that range (32768Hz).

author: metrologist
author_rank: Super Contributor
timestamp: November 13, 2018, 04:35:33 pm
content: I think the concern is with any mode that can resonate and loosen bonds.

author: cgroen
author_rank: Unknown
timestamp: November 13, 2018, 05:09:49 pm
content: Thanks for replies!Have any here actually seen this, or have you only heard about it ?

author: ataradov
author_rank: Super Contributor
timestamp: November 13, 2018, 06:21:03 pm
content: Only anecdotal evidence. I've been cleaning boards with 32 kHz Xtals for some time and I have never seen a failure. But this obviously does not mean that there was no subtle damage that may become evident later.I have never seen actual evidence of the damage actually provably happening.

author: Gribo
author_rank: Frequent Contributor
timestamp: November 13, 2018, 08:02:49 pm
content: I had failure (component out of spec) for a 26MHz crystal. Spec was 20ppm initial accuracy over standard temperature range (-10 to 50C), assembled product had 40ppm. We traced it to the ultra sonic cleaning process. Moved to standard washing, and everything was alright.
Cheap PCB service with castellated holes - Page 1
Forum section: electronics / general

author: 0xdeadbeef
author_rank: Super Contributor
timestamp: November 25, 2018, 11:16:32 pm
content: I'm sorry if that has been asked before, but I couldn't find any thread discussing this.So in a nutshell: are there any Chinese PCB services which support castellated holes without massive extra cost?I.e.for Elecrow, Seedstudio, PCBWay etc. the prices explode from $5 to $20-$25 for 10 very small PCBs (e.g. 15mm x15mm) when adding just a very few castellated holes.I'm aware of all the technical issues, but I don't care if they are a bit messy.

author: whalphen
author_rank: Regular Contributor
timestamp: November 25, 2018, 11:47:35 pm
content: I've used OSH Park for this. They are cost effective for very small boards. They don't do true castellations, but they will drill and plate holes on the edge before routing. This sometimes leaves extra tabs of copper in the castellation, but these can be easily removed with a small blade. Look at this description:https://docs.oshpark.com/tips+tricks/castellation/For a 15mm x 15mm board, the cost would be about US$0.60 each with ENIG plating and international shipping included.

author: 0xdeadbeef
author_rank: Super Contributor
timestamp: November 26, 2018, 06:13:39 pm
content: Thanks, I'll have a look. I'm just slightly scared that ordering from the US will cost me some hours at the customs office. I guess customs gave up controlling the massive amount of small packages from China while they always find the time to check stuff from the US.

author: 0xdeadbeef
author_rank: Super Contributor
timestamp: November 26, 2018, 06:59:20 pm
content: Anyway, I just ordered at OSH Park. As whalphen said, the prices for small PCBs are indeed very attractive.I ordered two different PCBs, each 12x with ENIG plating and castellated holes (0.8mm FR4, 2 oz copper) and paid a bit less than 12€ since the shipping was free.That's pretty much the best offer I could have hoped for.If they put a proper customs declaration on the envelope, I might even get around wasting half a day at the customs office.

author: 0xdeadbeef
author_rank: Super Contributor
timestamp: December 19, 2018, 11:40:05 am
content: The OSH Park PCBs arrived today. They posted them on the 7th of December and they arrived today (19th) which is pretty much what I expected. It just took a bit longer than I imagined between order (27th November) and production. Anyway, I'm happy I didn't have to go to the customs office as they did a semi-legit customs declaration (fake $10 while I actually paid $12.80).There was no bill/invoice included (which would have resulted in fun at the customs office) and the PCBs were just (loosely) put into the air wrap bagAnyway, the PCBs looks pretty decent. The solder mask is slightly off (no issue) and they seem to have shrunk the ground ring on the bottom, so there's a small gap between ground ring and border. Surprisingly they didn't shrink the ground ring on the top.Posted pictures in the project thread:https://www.eevblog.com/forum/projects/driving-a-cree-q5-led-with-one-nimh-cell-anything-much-better-than-an-ltc3490/msg1974011/#msg1974011
so what is this green cross?..newbie question - Page 1
Forum section: electronics / general

author: Martiniko
author_rank: Newbie
timestamp: November 07, 2018, 10:12:45 pm
content: Hi,I am a bit new to this with making PCBs and I have a question:What is this green cross in the middle of the image? (see attached image).Is it necessary to have it? (I have seen it in a lot of footprints)it´s a print screen from one of the parts that I have. (I am using Altium designer).Another question:What reference point (for origo in the footprint) should you use when you make your own footprints? pin number 1 in the footprint? or the center of the footprint? or it does not matter?

author: ANTALIFE
author_rank: Frequent Contributor
timestamp: November 07, 2018, 10:52:01 pm
content: The green cross is the centre of the component, I would leave it on there as it's just more info that might be useful for the assembly house. Plus it's on it's own mech layer so is not really "hurting" anybody.As for what centre point you should use, I think the IPC standard is the centre (of mass?) of a component. I would recommend using PCB Library Expert (http://www.pcblibraries.com/LibraryExpert/) when creating your footprint, as it generates IPC compliant footprint, so one less thing for you to worry about

author: Martiniko
author_rank: Newbie
timestamp: November 07, 2018, 11:08:41 pm
content: Ok, thank you for the information.I will check out that page you linked to.Do I need to put one cross in if I would make my own footprint?my theory is that it could be for the pick and place machine to know to what position to lift the component to. (but its just a theory of mine)

author: ANTALIFE
author_rank: Frequent Contributor
timestamp: November 07, 2018, 11:19:30 pm
content: Your call, again I would just use the program I linked as it takes care of everything.When someone sets up a pick & place machine they feed in a pick&place file which states the X/Y coordinates of all components, with each component usually being referenced to their origin/centre. There might be some places that also feed in the component outline Gerber mech layer
Can your PnP place this component? - Page 1
Forum section: electronics / general

author: olkipukki
author_rank: Frequent Contributor
timestamp: November 08, 2018, 02:32:26 pm
content: Not sure how it correctly called - is it some sort of a grip nozzle required?

author: capt bullshot
author_rank: Super Contributor
timestamp: November 08, 2018, 02:48:33 pm
content: Manufactures often sell this kind of connector with an additional thingy (e.g. an clipped on plastic part or a piece of attached kapton film) to ease PnP. This thing has to be replaced after reflow. The ones as shown look difficult for the usual vacuum based PnP heads.

author: SMTech
author_rank: Frequent Contributor
timestamp: November 08, 2018, 04:38:36 pm
content: ^^ what he said. This is why I advise not to use an SM connector without good reason. If you are working in volume or need to, fine, otherwise SM connectors can need tooling (bye bye labour saving) or available stock in a very specific part number that adds a pick pad to the connector, or placing with tweezers - maybe not as straight as you'd like. Here is a datasheet for a similar terminalhttps://www.toby.co.uk/uploads/publications/263.pdfwhere you can see the last letter denotes a variant with pick pad and its an option, Samtec are quite nice, datasheets are readable and part number easy to derive... unlike Molex.I can only assume some machines do use some form of gripper or the versions without pick pads would not exist, however plenty of machines don't have that option. Its not just male pin headers that have this problem, pin sockets can have the same issue as the holes dissipate too much of the vacuum,but some machines might not care or let you turn off the vacuum check for specific parts.

author: mrpackethead
author_rank: Super Contributor
timestamp: November 08, 2018, 06:37:31 pm
content: That would be a challenge for me.

author: hcglitte
author_rank: Regular Contributor
timestamp: November 08, 2018, 10:55:02 pm
content: What about U.FL / IPX connectors? My machine manages most of the time, but it's not ideal.https://en.wikipedia.org/wiki/Hirose_U.FL#/media/File:2_mm_SMD_UFL_Socket.jpg

author: ANTALIFE
author_rank: Frequent Contributor
timestamp: November 09, 2018, 12:08:41 am
content: Dealt with a similar connector before, we were lucky enough to have a nozzle that just fitted between the pins. But as others have said usually connectors like these come with a little plastic cap or a piece of kapton tape that you pick them up with

author: olkipukki
author_rank: Frequent Contributor
timestamp: November 09, 2018, 06:14:32 pm
content: Ehhh, seems like they can process a custom-made order, not in a hassle free way as Samtec, but still they can...QuoteAlternative, gripper nozzles might cost a fortunehttps://www.europlacer.com/feature/smart-nozzles/Quoteor

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 09, 2018, 06:33:26 pm
content: Or just a nozzle with a large rectangular face
Flex Rigid PCB in PNP Machine.  - Page 1
Forum section: electronics / general

author: mrpackethead
author_rank: Super Contributor
timestamp: November 07, 2018, 06:50:50 am
content: How are Flex Rigid PCB's run through Stenciling and PNP? How do you keep them flat?

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 07, 2018, 06:59:33 am
content: Custom fixturing or vacuum bed.The former could be as simple as a sheet of FR4 and some kapton tape

author: Mr. Scram
author_rank: Super Contributor
timestamp: November 07, 2018, 07:18:02 am
content: Good question. I'm wondering the same about full flex.

author: mairo
author_rank: Unknown
timestamp: November 07, 2018, 08:58:36 am
content: What Mike is saying. Custom fixtures is what I have seen mostly here in AU for the assembly and later for the test.

author: SMTech
author_rank: Frequent Contributor
timestamp: November 07, 2018, 12:12:59 pm
content: Pure flex PCBs go through the whole process on custom fixtures. Rigid-Flex, with suitable Panel borders should be able to go through fairly normally if you can't justify a fixture, tho' you may need to have more than your std board support to keep it properly supported. There are some good whitepapers/articles out there discussing them, flex is very hygroscopic so how it is stored an treated before reflow is critical or it can delaminate, the adhesive in the flex layer is also quite sensitive (Low TG) which means the fixture might well shield the flex section or you might shield it with some form of cap either fitted by the SMT or popped on between placement and reflow if you have a suitable gap between the two.
What is glue logic - Page 1
Forum section: electronics / general

author: YRTYRYTY
author_rank: Newbie
timestamp: October 27, 2018, 06:51:09 am
content: HelloWhat is glue logic where it is used

author: BravoV
author_rank: Super Contributor
timestamp: October 27, 2018, 07:02:27 am
content: क्या आपका Google टूटा हुआ है?

author: ataradov
author_rank: Super Contributor
timestamp: October 27, 2018, 07:07:53 am
content: Someone really sucks at making AI bots.Dude, if you are reading this, give up, go work at McDonalds. Doing AI is not yours.

author: ataradov
author_rank: Super Contributor
timestamp: October 27, 2018, 07:21:39 am
content: Quote from: YRTYRYTY on October 27, 2018, 07:20:23 amYou don't use it, you sniff it. Just like a regular glue, but it gets your levels all high.

author: ebastler
author_rank: Super Contributor
timestamp: October 27, 2018, 07:43:39 am
content: Quote from: YRTYRYTY on October 27, 2018, 06:51:09 amYou came to the right place, the "manufacturing & assembly" forum. But you got the term wrong: It is called "logic glue", and is what they use to attach those logic chips to the circuit boards.

author: BravoV
author_rank: Super Contributor
timestamp: October 27, 2018, 07:53:34 am
content: The OP is now taken care off... move along.

author: ebastler
author_rank: Super Contributor
timestamp: October 27, 2018, 08:01:03 am
content: No, he is back already, in the Beginners section, this time calling himself RTBRETRT.Utterly glue-less...

author: Proto
author_rank: Contributor
timestamp: November 06, 2018, 06:12:06 am
content: There is a such a thing as "glue logic". It refers to using low-level logic functions from families of parts like 74HCXX or 4XXX families of CMOS for example to allow more complex chips to interface to each other. It can be as simple as inverting a control signal so it has the correct active level between 2 parts or adding a logic gate to qualify a signal between an output and an input with 1 or more additional signals. There are other times when a flip flop or level translator, buffer, etc that might have to be used on an individual signal or parallel bus. These becomes the glue to make parts work together. The object of good complex chip and system design is to eliminate the need for any "glue logic", However, there are times when chips are used in ways that were not expected. An Intel I9 9th generation processor contains 7 or 8 billion transistors compared to a logic gate, inverter or flip flop with tens of transistors. This makes glue logic a real pain in the ass to use for the wasted space per function. As a result, there are single function glue chips with for example 1 inverter instead of 6 which are in a 74HC04's original packaging along with the use of much smaller smd packaging.
For Sale: Various 2nd hand PNP machines; Yamaha Juki Samsung Panasonic - Page 1
Forum section: electronics / general

author: mrpackethead
author_rank: Super Contributor
timestamp: October 29, 2018, 08:18:41 am
content: A vareity of good working 2nd hand PNP machines are avaialble ex China.YV100-ii with ~10,000 hours approx price $10k USD,. Supplied with some feeders. ( this is good for down to 0402 ).. Good support for afternmarket parts as well. ( this is 1500kg or so! )I'm not selling them, but just had a great experience with the guys who are.. This is a way of getting a serious PNP without the big cost. It will take you some effort to learn to use it, but you can get a working machine for a fraction of the cost of a new one.ksunsmt.com is the company...

author: Reckless
author_rank: Frequent Contributor
timestamp: October 31, 2018, 02:37:46 pm
content: For anyone in US, I have some extra pick n place machines I am not currently using, Juki 740, Juki 730 chip shooter, Juki 760. You can avoid the 25% special china tax and save on shipping. We have excellent resources for programming. The older Jukis are much easier to work on.

author: mrpackethead
author_rank: Super Contributor
timestamp: October 31, 2018, 05:57:59 pm
content: Quote from: Reckless on October 31, 2018, 02:37:46 pmYamaha ( and Juki ) machines are not subject to the US tarrifs against China, becuase they are not made in China. Bit of FUD there Reckless.What price are you looking for your machine
PCB assembly - minimum distance b/t components? Good China/EU factory? - Page 1
Forum section: electronics / general

author: 3dgeo
author_rank: Frequent Contributor
timestamp: November 03, 2018, 07:18:11 pm
content: Hi,In a few month time I'll need to assemble two sided ~210mm x ~95mm PCB (components on one side, up to 15 SMD different components, up to 80 in total, minimum 100 PCB), so I need some assembly factory recommendations in China and EU, and specs for spacing if possible. I thought this is a perfect place to ask.I know JLCPCB has best prices for making PCBs, but I need to assemble it as well.My biggest concern is this 1210 RGB LED ring, they are very close to each other (~0.2 mm) and rotated every 12 deg.:LEDs themselfs:https://www.aliexpress.com/item/Wholesale-100pcs-RGB-POWER-TOP-1210-3528-SMD-SMT-PLCC-2-LED-Red-Green-Blue-New/32384196929.htmlAny help/advice is highly apresheated.

author: KL27x
author_rank: Super Contributor
timestamp: November 04, 2018, 02:09:03 am
content: You need a starting point that is more than a picture of an unpopulated PCB? Are the LED dimensions actually larger than the edges of the pads? (If not, I doubt you have a problem; just get some quotes).Like maybe make an outline for your library part, using the maximum tolerable dimensions in the datasheet. Then you can see how much clearance you actually have to work with in your PCB CAD software. Then you would have a number to put in "additional information" when you submit a quote.

author: 3dgeo
author_rank: Frequent Contributor
timestamp: November 04, 2018, 08:12:16 am
content: Quote from: KL27x on November 04, 2018, 02:09:03 amThank You for Your reply, I know for sure that LEDs do not overlap, those silk screen squares represents LED size accurately, tho smallest distance between LEDs is ~0.2mm, can that be an issue when it comes to a component placement?

author: SMTech
author_rank: Frequent Contributor
timestamp: November 04, 2018, 02:53:43 pm
content: 0.2mm shouldn't be a challenge, that is well within the placement capabilities of most equipment, the key to delivering it here will be in how accurately the alignment system can see the device, potentially making it a job a machine with laser alignment might do more accurately than camera. I place quite a few LEDs of this style but I have the recognition tuned more towards sucessfully recognising the device than to getting superaccurate alignment, all the same its pretty consistent, less so when placing domed versions.Where you have to be careful IME with very close proximity is with things like SOIC or Opto packages, they tend to have a distinct seam in the moulding which can sometimes challenge the min/max dimensions in the datasheet. Equally the accuracy for passives "chips" is always lower on placement machines as they are volume parts where accuracy is not supposed to matter, start sticking those right next to each other and now and again it might cause problems..That said look at thisif your contractor has issues, either its closer than you think or they aren't very good. I don't think special instructions should be required here.
Keypad Backing Thickness - Vacuformed Enclosure - Page 1
Forum section: electronics / general

author: MudAndSnow
author_rank: Contributor
timestamp: October 26, 2018, 06:05:52 am
content: I want to make an enclosure for a 4x4 membrane keypad out of ABS or similar material. The enclosure will be slightly larger than keypad and shaped to have rounded edges using vacuum former.The abs sheets are surprisingly expensive, specially for thicker ones. Which makes me want thin sheets but of course not so thin that it flexes noticeably when user presses buttons.Any ideas what an ideal thickness would be?If you have other suggestions please feel free to share.Keypad:https://www.amazon.com/WINGONEER-Universial-Switch-Keyboard-Arduino/dp/B06XHFC19G/ref=pd_aw_vtph_421_tr_2?_encoding=UTF8&pd_rd_i=B06XHFC19G&pd_rd_r=067f9398-d8e3-11e8-943e-3f50e486d3b4&pd_rd_w=89K8S&pd_rd_wg=nUgTi&pf_rd_i=mobile-dp-sims&pf_rd_m=ATVPDKIKX0DER&pf_rd_p=61cf5fd0-cfc9-447f-a425-f14760645161&pf_rd_r=A4M7MGENPZNFE2RV4VRR&pf_rd_s=mobile-dp-sims&pf_rd_t=40701&psc=1&refRID=A4M7MGENPZNFE2RV4VRRABS sheets:https://www.amazon.com/Thickness-FYBREX-Textured-Breakage-Resistance/dp/B074NZ4TK1/ref=mp_s_a_1_3?ie=UTF8&qid=1540533377&sr=8-3&pi=AC_SX236_SY340_FMwebp_QL65&keywords=abs+sheet&dpPl=1&dpID=41ihs%2BqUmxL&ref=plSrch
Low cost rubber bands for our enclosures - Page 1
Forum section: electronics / general

author: Martin F
author_rank: Regular Contributor
timestamp: October 24, 2018, 08:25:36 pm
content: Hi all,We have a set of aluminium enclosures where we need black rubber bands at low cost.Ideally, they should have a diameter of 5 cm, width 0.5-0.8 cm and thickness of 1-2 mm.We're looking for something along the lines of these from Takachi:http://www.takachi-enclosure.com/data/c16-17/SIB.pdfAny idea of other places we can get these?Thanks!Martin

author: voltsandjolts
author_rank: Unknown
timestamp: October 24, 2018, 09:15:18 pm
content: o-ring

author: kosine
author_rank: Regular Contributor
timestamp: October 25, 2018, 01:32:33 pm
content: Can't think of a simpler solution, though you'd probably want a rectangular o-ring like this:https://www.alibaba.com/product-detail/Rectangular-o-ring-rubber-seal-ring_60056051532.htmlContact some o-ring manufacturers/suppliers and see if they can help. A fairly soft material would be better, something around 60A shore hardness should be about right.
Advice on Sourcing LCD Modules Direct From China - Page 1
Forum section: electronics / general

author: techy101
author_rank: Unknown
timestamp: October 24, 2018, 02:58:26 pm
content: I work for a small electronic device manufacturer in the USA and am designing a product which requires a 128x64 ST7565 COG Graphic LCD module. I've never dealt directly with Chinese suppliers but am looking into it due to the dramatic cost difference compared to domestic companies like Newhaven (though their website says many parts are direct from China but are roughly 3x the price).My questions are:How to select a reputable manufacturer. There are a ton on Alibaba and Made-in-China but it's a bit overwhelming. We have samples from EastRising (BuyDisplay) and have been happy with them but have no clue how they are for small volume production ( < 500/yr).Can you order components like this directly from these Chinese manufacturers without having an import license? Again, the digging I've done has quickly become overwhelming. We're dealing with purchases of $500 - $700. I know no one can truly answer this question for our specific case, but I'm hoping someone who has dealt with this can point me in the right direction.Do companies like DHL handle the import logistics like tariffs for you?Thank you!

author: SMTech
author_rank: Frequent Contributor
timestamp: October 24, 2018, 03:56:37 pm
content: What Newhaven price are you basing the x3 cheaper on? In the UK for example if I go to Plusopto for Winstar displays and ask for 500, that price would be be not far off the 1off number on the Newhaven website. The catch would be a lead time often IRO 12-14weeks if its not on the shelf (e.g VATN). By going with the recognised reseller you might even be able to say, I want 500 over the next 12 months, get the 500off price and receive them in drops with the reseller holding the remaining stock. China direct by contrast tends to be a cash-up-front sort of a deal

author: techy101
author_rank: Unknown
timestamp: October 24, 2018, 04:06:18 pm
content: For some reason I'd remembered theNewhavenone being $20, but it's $16. A comparableEastRisingdisplay is $6.71. Unexpectedly, the EastRising unit actually looks better too.I feel silly now that I haven't inquired about the volume pricing yet.The cash up front issue is one of the things that makes me nervous, as does the reliability of ongoing stock/production and consistency.
Rigit flex pcb - Page 1
Forum section: electronics / general

author: bug13
author_rank: Regular Contributor
timestamp: October 19, 2018, 07:50:58 am
content: Hi guys,I need to make a rigit PCB, how do you usually do it in a software that DO NOT support this? I am using Altium 09.Assuming I want to make a 2 layer PCB, do I just add a extra layer and tell thebfab the extra layer is the Flexi copper layer. And in gerber files, I just specify what area is rigit and what area is Flexi?Thanks guys!

author: Niklas
author_rank: Frequent Contributor
timestamp: October 20, 2018, 08:15:48 pm
content: 1. Check what stackups your PCB manufacturer can produce and select one that fits your needs.2. Make the layout as if it was a standard rigid PCB. The difference in the newer Altium Designer is that you add the split and bending lines in the board planning mode, but those are not exported with the Gerber files. The only benefit is that you can bend the flex areas and see how they fit into the mechanical assembly in the 3D view.3. Avoid via holes in the area close to where the flex exits the rigid part (>=1mm, or whatever your PCB manufacturer specifies). No vias or sharp bends in the flex region.4. Add an additional mechanical layer where you draw up the split lines between rigid and flex. Mark the different areas Rigid and Flex.5. Export Gerbers and Excellon drill files including the additional mech layer.
FPGA Inspection? - Page 1
Forum section: electronics / general

author: mrpackethead
author_rank: Super Contributor
timestamp: October 17, 2018, 08:19:10 pm
content: Can't avoid BGA's any longer. I have been able to place them accurately, on the pcb..What options do i have for inspection / testing, without spending a truck load. With 400+ pins, there is a chance of a issue.

author: mrpackethead
author_rank: Super Contributor
timestamp: October 17, 2018, 08:23:01 pm
content: Quote from: mrpackethead on October 17, 2018, 08:19:10 pm

author: asmi
author_rank: Super Contributor
timestamp: October 17, 2018, 08:33:36 pm
content: Keep breakout vias open on the bottom and do a JTAG boundary scan? But you've got to be wary of shorts at the bottom by runaway solder paste from decoupling caps under BGA.It all really depends on ball pitch. At 0.8 mm and up precise alignment is not important as the package with realign itself (to the point of course). I'm yet to encounter BGA soldering failure, but I'm only a hobbyist so it's not that much of a reassurance, but still considering how primitive the tools I'm using are (cheap-ass IR reflow oven, manual placement, only recently did I buy a manual stencil printer) I'm sure you'll be fine.Anyway - what I do with my boards is create a test design that "wiggles" slowly such that neighboring balls wiggle at different frequency (to detect shorts), and then I go pin-by-pin and check if what I have on it matches what I expect. For balls that go to DDR3L I just create a test design with memory controller and MCU (really easy to do in Vivado) and run a memory stress test for several hours.As I suggested many times here buy a bunch of cheap QSPI flash chips in BGA-24 package (can be had at lower than $1/piece) and refine your process with them. Larger parts are really "more of same", unless we're talking about really large (1000+ pins) packages.
V-Score Panelization Questions - Page 1
Forum section: electronics / general

author: 1276-2449-1-ND
author_rank: Regular Contributor
timestamp: October 16, 2018, 01:03:14 pm
content: A quick question about v-scored panels (no routing/milling):Should each separate PCB outline ("Dimension" in Eagle-speak) be included with the panel along with the outer panel outline? Or should the individual outlines be removed when adding them to an exclusively v-scored panel?From looking around it looks like it's done both ways. There's too much English in my question for the fab to answer coherently.I ask because Eagle cuts out dimensions-within-dimensions (with Board Shape Detection enabled) and it looks funny, and I don't know if the individual PCB dimensions are used for anything at the fab for these types of panels. Sample in first picture.Which layer should the V-Score line be on (I used the Eagle default 102)? Where should that layer be included in the Gerbers? Should it be annotated on that layer (as shown in the second picture)?

author: Kean
author_rank: Unknown
timestamp: October 16, 2018, 01:18:15 pm
content: I’ve always done it with just the outer dimension plus the v-score lines (annotated) all on the dimension layer. Never had a problem or query using multiple fab houses.

author: Kean
author_rank: Unknown
timestamp: October 16, 2018, 01:22:54 pm
content: No problem if you put the v-score lines and annotations on different layers, and even have the panel and individual PCB outlines on different layers. I often do that in Altium, but don’t think I’ve bothered in Eagle.The important thing is to include all the appropriate layers needed when generating the dimension Gerber to be sent to the fabricator.

author: mrpackethead
author_rank: Super Contributor
timestamp: October 16, 2018, 07:09:28 pm
content: I normally have an outline layer, that is included on *every* layer of the gerber.I supply another gerber that has the vscores, another with tab routing. It seems to work ok for me.