add a component to the bottom of a PCB?
Is it possible to add a component to the bottom of a PCB? Starting with a simple example: Say I have two boards that I want to sandwich together. The bottom board would have a male pin header on its top layer and the top board a female pin header on its BOTTOM side. Is that possible?
If not I gather one would just align vias on the top board and the boards could be soldered together :/
I should note, if this has been asked and answered elsewhere please point me to it. I ran a basic search and didnt find an answer. thanks
Okay, I just realized I'm a silly goof. Of course with a pin header you and place it on the bottom because the vias go all the way through top and bottom so one would decide if the part is on the top or bottom when the solder it to the board ;)
And as there are no "pads" in fritzing yet (no SMD components, all through hole) then all the parts hold the same rule. All vias go all the way through the board hence, you decide top or bottom later.
Anyway, hopefully this helps other people out there... you know, other people two high on caffeine and lacking sleep ;)
As you say, through-hole parts push down through the top layer and reach through to the bottom layer, and can be soldered on either side. There is some explanation of this in the blog (http://fritzing.org/news/double-sided-boards/).
There is some support in Fritzing for SMDs, but it's not well-tested, and you would have to create custom SMD parts using the parts editor. Once the parts editor is open, you would choose an SMD footprint for the PCB view of the part. There are both SMD and through-hole footprints available in the parts/contrib/pcb folder, and you can also import from Kicad .mod files or gEDA .fp files.
However, in Fritzing, you can only add SMDs to the bottom of a single-sided board (i.e. for home-brew etching). On a two-sided board, the SMD would always be added to the top layer.
I +1 putting components on the bottom part. That single thing would make Fritzing worth using instead of eagle.
I'll add it to the issue tracker. Not sure when we'll get to it though. If other people out there really miss this feature, let us know.
+1 -- I'd love to see this feature. The project I'm currently working on will require parts on both sides (SMD LEDs on one side and chips/power on the other). I suppose as long as we use parts with pins we could simply mount them on the back side using through holes but we'd really like the flexibility of full SMD/part capability on both sides.
+1 -- I would also like to see this feature included in Fritzing in the future.
+3 this side.. I take it this is still not a feature? We're going very small and need SMD both sides.. Great product though!
Given the number of requests for this feature, we are definitely bumping up the priority. We're not at the point of being able to set a date though.
I'm real keen for this feature also, love to know the date :)
Another +1 for this feature please! It would be very handy for shrinking boards a fair bit.
I just added in some experimental code that will allow you to place SMD parts on either the top or bottom layer of a two-layer board. Assuming this doesn't cause cataclysmic problems, you can expect to see this feature in the next release. Putting through-hole parts on the bottom layer is harder, so I still can't give you a date for that.
This news just made my day. I literally just hit a wall in my project that requires SMDs on both sides and just found this thread. I was worried I may end up having to migrate to another environment like Eagle, but now there's no need! Thanks!
We are always happy to make someone's day. At the risk of spoiling it, the feature isn't released yet so you will have to build Fritzing from source if you need SMDs on the bottom right away.
I've really happy that the SMD on the bottom is happening in the next release, can you give me/us an estimate of when the next release might be? as I've got a couple of projects that require this and my time line is getting shorter :(
There's really no date set right now--both projects we are working on (new parts editor, lots of new parts) are a long way from the finish line. I suppose we could consider an interim release with only this new feature...
I for one would be real keen on seeing the SMD components on the bottom and if this could be done with an interim release then that would be fabulous. I know this probably adds more work and respect this balanced against getting other things done.
My vote interim release :)
I have mixed feelings. Part of me would love to see the interim release today, but I'm also very excited for the updated parts editor and new parts!
I'm sure the Fritzing powers that be will make the right decision. :)
I guess we'll do an interim release once we have a sense that we've reached a point of reasonable stability. I would guess that's a couple of weeks away.
+1 - would be handy (although not essential) for a project I'm working on right now.
This is already available for SMD parts only in the current release. THT parts will be a later release.
Cool. Lol. I'm so bad at keeping up with your developments. :)
My project is a very small two-sided board with all SMD parts. I'm using version 7.10b.
To clarify what you can apparently do: I could place a pad on the bottom, and route wires from it to vias. Then I tried to place an FET in the SMD SOT-23 package on the bottom. It appears that the three lands are on the bottom (they are dark orange). However, I could not route from those pads to a via. (The lands of an SMD part on the bottom cannot be routed from the top or the bottom.)
To restate: if you are speaking of 'SMD parts' in the general sense, you can place them on the bottom of a two-sided board, you just can't route to their lands. An exception is: 'parts' that are just pads.
If that is the case, for a very small design, could you make a functional PCB (if you don't care about the schematic or breadboard) by putting a pad overlapping the lands of SMD parts on the bottom (and routing from vias to those pads)? I tried Export for PCB and the PDF files apparently have correct copper on the bottom, with the lands for the SMD parts, the pad, and the vias. Also, I'm wondering if the Fritzing Fab would reject such a design, where the schematic and breadboard was a garbled mess, but the designer was confident that the PCB was OK.
My project is the smallest board Fritzing would let me make, 12.7 mm square with only 4 parts, one of which I want on the bottom. Until now, I have been deadbug soldering the parts together, but now I desire a tiny PCB board. I suppose such a use case is very rare among Fritzing users.
You should be able to draw traces from SMDs on the bottom layer. Make sure the bottom layer is active (there is a button for toggling the active layer in the button bar at the bottom of the window).
I would also recommend upgrading to 0.7.11, since I think I remember some bug in this regard in 0.7.10.
OK, I will upgrade. There have been a few posts about this subject. Most seem to say you can only put a SMD part on the bottom of a single-sided PCB (but I want a double-sided board, with SMD parts, routable, on both sides.) If that has changed, I don't know when it changed. But I will try it.
SMDs on the bottom layer of a two-sided board have been available since 0.7.9. There are two ways to place an SMD on the bottom.
1. If you have an SMD already on the top layer of your sketch, use the 'layer' drop-down in the Inspector to switch it to the bottom layer.
2. if you have a through-hole part in your sketch, make the bottom layer the active layer, then use the Inspector to change to an SMD package.
I upgraded. I still can't route to an FET in a SMD SOT-23 package on the bottom, but I see that I can route to a capacitor in the SMD 1206 package, on the bottom. So now I suspect that the FET part is one that I made, and I failed to make it properly. I will study the problem and get back to you.
The part that won't route on the bottom is one I created with my program "Fritzing Part Scavenger" which creates a "Mystery SMD" family part from any PCB SVG file in the Fritzing directory that it thinks is an SMD footprint with the chosen number of pins. I could not debug what I am doing wrong in creating the part .fzp file. But since it seems like Fritzing is moving away from .fzp files (keeping most data in a SQL db) I am not going to debug it further. I don't understand some nuance about the .fzp files.
But, when I run my bad part through the Part Editor (making some trivial change and then saving it), after that the part routes on the bottom (little square appear on the pins and I can drag from them.) And any new instances of the part are routable. My conclusion is that there is some subtle difference between an imported part and a part that the Parts Editor writes back to the db?
For my project, I just used existing parts (transistor and resistor) with SMD packages, even though they are not really the parts I want (a diode and other 3-pin chips) and one SMD package (805) is adequate but not really the best SMD package (say SOD323 for a diode.)
I still think the idea of the Fritzing Part Scavenger is useful, at least for the use case of users working in SMD. I don't really want to use the Parts Editor every time I need a new SMD package, when they are already out there and have the right number of pins and often the right pins names in the SVG PCB file. For example, the SOD323 (SMD package for a diode) SVG file is in the Fritzing directories (I think it was gleaned from GEDA) but I don't know where it is attached to any part and it isn't under the "Rectifier" part where I expected it. I know I could find it using a file browser, and use the Parts Editor to create a new part pointing to that SVG PCB file. The Fritzing Part Scavenger finds it for you and does all the work (if it didn't have this bug, and if the Fritzing Part Scavenger was packaged better for distribution.)
Also, you could easily extend the File Part Scavenger to change the pinout of a part, which is another common use case.
Thanks for your work.
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