Creating your own custom hardware (printed circuit boards)

hey everybody today i want to talk about custom hardware printed circuit boards and making embedded systems that you can actually deploy out in the wild so welcome back everybody most of the content on this channel is software based i have done a few videos on embedded systems i'll link to those in the description and some of those videos talk about how we write software that interacts with hardware but i've been thinking for a while that i actually want to do a video on making hardware and then our friends from next pcb contacted me they wanted to sponsor a video i wanted to provide some discounts to my audience some more details on that later and down in the description but the point is is today seemed like a really good day to talk about custom hardware now if you've watched this channel at all you know that i love software but when i started getting into embedded systems back in 2005 2006 one of the things that i actually really loved about embedded systems was that i actually got to start developing hardware as well as software and that's really cool when you find that you have a need that you you can't find a commercially available product that provides the hardware capabilities that you need it was just really awesome as a software guy who hadn't really gotten into this to be able to then craft my own hardware that could accomplish the things that i needed done and i see this over and over again in my students when i teach embedded systems so usually when i start teaching students embedded systems we're working with stuff like this we've got development boards we have some sensors components connected through breadboards and jumper wires and this is really good for understanding the basic concepts of what we're working with but it doesn't take very long with this kind of setup before students raise their hand and say hey how could i make something that actually like that i could wear that you could take for a run that i could actually feel like how can i make a real device something that feels like something that you would buy commercially and so that's where today's discussion comes in the answer is that usually we're going to print a custom circuit board something like this which is basically going to take the circuit design that we tried out on our breadboard and condense it down into a single board that's hopefully smaller and is going to do the same thing only hopefully better because we won't have jumper wires all over the place so let's say you've got a circuit design something that you've tried out you've got an idea you think it's going to work and you want to take it to the next level today i want to talk about how that process works so now the first thing you're going to need is some software so we have a few options altium eagle and kycad there's also easy eda i've heard is nice i haven't used it it's a web-based option now i've listed these options here because they're the options that i'm familiar with also because they represent three points on the price spectrum with altium being most expensive kiked being free and open source and personally i usually use eagle which is the one in the middle but any of these three are gonna work now i don't have time to do a deep dive into eagle today and that's okay because the folks over at sparkfun have some great eagle tutorials i'll link to those also in the description and no they're not paying me to say nice things about them these are just the eagle tutorials that i recommend to my own graduate students when they come along and want to learn how to do this but the point is today i'm not going to get into the weeds i want to stay high level and talk about the process and then of course you let me know if there are pieces of the process that you want me to dive deeper into in a future video so the first thing we're going to design is our schematic this is the logical layout for your circuit it has the components that your board's going to have on it and the connections between components at this stage you don't really have to think about where things are going to go on your board or even how big your board is going to be this is just where we draw out our circuit we look at how the electricity is going to flow how things are going to be connected so here's an example schematic from one of my projects the schematic phase is really like i said one of just connectivity you're looking at what are my components and how are these things all connected together so here you're specifying values and names and things like that but not actual layout it's really just the logical layout for how things are supposed to be put together in this particular circuit regardless of which software package you're using to edit your schematic typically you have access to a bunch of different component libraries so you don't have to design necessarily all these parts yourself you'll have resistors capacitors inductors jumpers as well as some of your integrated circuits these are often provided either by the manufacturers or someone in the community who just happen to make a package for you and that can be really really handy and so then you can typically just drop these in and place them wherever you want in your schematic so nothing complicated here well i mean you can make it as complicated as you want it's a circuit so it could be really complicated but the actual task of bringing in these components and adding them in and wiring them up that's not particularly complicated okay now once we have our schematic then you also want to produce a layout this is the stage where we start thinking about sizes and dimensions i'll just show you an example layout this is the layout for the board we've been looking at and you can see if we come down here we specify the size of the board we also we can come in here and we can see like there's a place for an antenna to come in there's a footprint for that and you've got connectors for headers and a bunch of these different components so this is just specifying where everything belongs these footprints correspond to the packages that were in the schematic so each component in the schematic has a footprint here and then we connect those components with copper traces in this case those are all shown in red and note you can also have multiple layer boards so like right now all of these are all on one layer that's why they're all in the same color i could have boards that are two layers deep or four layers and so as things get more complicated sometimes you need more layers but this is a simple example it's really just using the one layer and then we use the bottom layer so it's a two layer board we use the bottom layer as a ground plane now at this point you may have a ton of questions depending on how much experience you have you might be saying wait hold up what about routing and trace widths and should i use through-hole or surface mount components and of course like i mentioned before there is a lot we could discuss in here but today i just want to keep things at a high level and talk about the process we can definitely discuss deep dives into a particular aspect of circuit board design if there's things that you're not seeing in existing tutorials and if you don't mind learning hardware from a person with three computer science degrees who doesn't have very much formal electronics design education i'm pretty much a self-taught electrical engineer but once we have our schematic and our layout we are ready to make our boards at this stage we need to identify a manufacturer well we don't need a manufacturer it is possible to etch your own boards with a laser printer and a bunch of chemicals and it's one of those things that maybe you should do once just to say you've done it but i find that it makes a lot of mess and generally it's not worth the effort that it takes to do it myself so if i'm going to print this board i'm going to use a manufacturer and the manufacturer that i'm using as an example today is next pcb which is our video sponsor for today now there are a lot of different pcb manufacturers out there one nice thing about next pcb is they specialize in small run orders so a lot of times when i'm making boards i just want to see if it works i want to make a few devices i don't want to make 100 or 200 or a thousand devices i just want to make one because there's a really good chance that my first run is gonna have a problem with it and so i need something low-cost where i can just order a couple of boards and as i mentioned at the beginning of this video next pcb is providing a discount to anyone watching this video i'll put the links down in the description but these discounts can bring your price down even further especially on your first order and i'm guessing no one's gonna complain about that okay so now regardless of who you go with the next step is generating your gerber files no this has nothing to do with baby food gerber is just a standard vector format that has become this standard for sending pcb designs to manufacturers and so whatever software you're using that software is going to be able to generate gerbers for you so here in eagle you use the cam processor to generate gerbers and we can go through and we can look at the different layers and and of course we can customize some things here i'm just going to leave everything as the standard defaults right now and then using those defaults i'm just going to export these out to my hard drive pretty easy now in this stage it's really important to keep in mind and take a look at the manufacturer's instructions now this is because each manufacturer has different limits they may limit how thin traces can be how close together elements can be and you don't want to put something in your board design that they can't actually make so usually i find the defaults to be good enough they usually work but you just want to be careful so you don't end up spending money and waiting for shipping just to find out that your boards you ordered don't work one other thing at this stage that i think is really cool is that next pcb also offers their own free analysis software they call it next dfm it's free and it's there to check your design files for you just in case you happen to miss something in their limitations and it will basically take a look at your design files and help identify errors before you order which can also save you time and money so i definitely want to point that out okay so now once we have our gerber files then it's time to actually order our printed circuit boards i'm going to just demonstrate how this works on the next pcb website and this process will vary a little bit based on which manufacturer you go with basically i'm just going to go in here and upload my gerbers to get a quote and then in addition to uploading our gerbers you're going to come down here and you can see there's a bunch of different options there's things like do you want your boards to be printed on fr4 that's the default but there are a few different options that you can see here you can select how many layers you want to print what the board type the size a lot of this is going to be populated automatically when i upload my gerbers you're also going to specify how many you want to make and the color of the solder mask and i'm not going to go through all these details there are a lot of them the main thing to keep in mind is that most of the time the defaults work great especially for a first project where you're just testing this out and going with the defaults often means less customization for the manufacturer which means your price is usually a little bit better so if this is your first pcb i would stick with green and you know white silk screen and standard pcb thickness and all of that just because that's going to keep your price down and it's going to keep your shipping time faster because it means they don't have to configure things on their machines differently they can just run your job with the same settings that just about everybody else has now if you have specific needs especially once you know what you're doing then feel free to customize to your heart's content okay so now once you have ordered your boards then you're gonna have to wait a certain amount of time that depends on the manufacturer where they're shipping from and of course during this pandemic sometimes shipping seems to be taking a little bit longer than usual but once your board arrives you're gonna get something like this right this is a purple one let me grab so this is this is probably more like what your first one's going to look like now this one has kind of a funky shape there's a story behind that which i won't go into but it was for a wearable device and it just we needed to fit a component right here in this hole and so that's the size and shape we went with now when your boards arrive you're not quite done now the thing is if you look at these boards you notice that they don't have any components on them what you really want is a board that looks like this that has its components already assembled and so that's the final stage in our manufacturing process is how do we get it assembled how do we actually put the components on there now you have some options here as well usually if this is a very first run and i don't have a lot of confidence whether this thing is going to work i will often just do these myself i can use a soldering iron i can use a reflow oven which i have available in my lab i've seen people use pancake griddles and toaster ovens to do this there are a wide range of options available to you as you get more confident or if you have a bigger budget and you don't mind spending the money and or you just don't know how to solder stuff then the other option is you can also pay someone like next pcb or another manufacturer to actually assemble your devices for you in this case you just you can either tell them what to order and they will order it and then they'll assemble your boards for you or you could ship them the parts you order them yourselves and ship them to them and you just tell them how you want them to actually assemble the board and then they will go ahead and build it for of course a price and that's definitely the way to go if you're making a lot of boards if i'm manufacturing a device if i'm making thousands of these things there's no way that i'm going to assemble them one by one by hand that just takes too much time it's not worth the effort but if i'm only doing one and i think maybe i want to make sure this thing really works and i want to be able to test stuff out as i go then it often does make sense in my opinion to solder things and assemble them by hand and so i know i stay pretty high level and there's a lot of details that i have left out in this video hopefully we'll pick some of those up in future videos but i hope at this point it gives you an idea of what the process looks like when it comes to making printed circuit boards and your own custom hardware and i hope this gives some of you out there who are just thinking about getting into this a little more confidence this is really not that crazy difficult to do you can do it thanks again to nexpcb for sponsoring this video and best of luck to all of you as you get started making your own printed circuit boards and custom hardware as you expand your repertoire outside of just software because in my opinion that's when embedded systems start to get really fun is when you're playing with both i hope this is helpful drop this video a like if you enjoyed it subscribe if you don't want to miss my next videos and until next time i'll see you later

Channel: Jacob Sorber

Views: 37,204

Keywords: custom hardware, custom hardware fabrication, embedded systems, custom circuit boards, custom printed circuit board, custo pcb, printed circuit board, print your own hardware, custom pcb, printing custom boards, pcb printing, hardware fabrication, designing custom hardware, designing boards, printing boards, printing hardware, pcb design, electronics projects, printed circuit board manufacturing process, printed circuit board design, custom pcb board

Id: 9zU92H_CLVI

Length: 12min 36sec (756 seconds)

Published: Tue Jan 26 2021