The Importance of Datasheets One of the things I really learned doing this kind of stuff was the importance of datasheets. As far as I'm concerned, if a part doesn't have a datasheet, I don't use it. And I would go so far as to even say a datasheet in PDF format. They are important to use, to download to a specific directory on your computer, and important to actually use.
Datasheets can give you the dimensions of the part (like how they should be laid out on a PCB) as well as critical information as to their voltage rating, current carrying capabilities, as well as their function. Good datasheets also include any discrete networks that are important to operating the component well (you shouldn't have to go hunting for related circuit designs that are needed to successfully use the component...though this is basically accepted culturally that you must). For me datasheets are a must in that there is always some piece of information I need but can't find. Datasheets help you avoid that long waiting time that it takes to go find the missing information and getting back to designing. Make a directory called datasheets, maybe even in your downloads directory so that when you see a component you like or already have, you have every possible piece of information on it. This is key to any kind of serious hobbyist work IMO. On Thursday, February 2, 2017 at 2:09:39 PM UTC-7, woody stanford wrote: > > OK, here is a short primer on how the good guys build things in a serious > hobbyist setting. > > The development is done in 2 main stages. Breadboarding, and PCB > construction (with presensitized board). > > The reason why the breadboarding phase is because the Inet is great, but > you can't believe everything you read on it. What you want to do is look on > the WWW for ideas and then breadboard them out. Once you get them reliable > and you undersand their operation, you can use the technique in your > personal projects. > > How you do this on a budget (as it is the Great Recesion) is you get cheap > Chinese breadboards on ebay for $5 a piece free shipping. Like here, > > > http://www.ebay.com/itm/830-Tie-Points-Solderless-PCB-Breadboard-MB102-65Pcs-Jumper-cable-wires-/231412564779?hash=item35e143832b:m:mlV4jkc4DpzzqjQsn-zO0-w > > The latest and greatest idea, the only downside is that it takes longer > than a week to get your stuff in but the price is right. You can also get > broken out sensors and the like for dirt cheap (basically mounted great > stuff the big guys use in smart phones and tablets). $5 per component is > typical if you know where to go. > > What you do is peal the backs off them an mount them to a 2' x 2' piece of > plywood you can get at Home Depot. And you are ready to rock. next step is > to find inexpensive, reliable power. A cool thing I've been playing with is > tablet bricks because they are reliable, ubiquitous and a lot of them > deliver a strong 1.0 Amp or 5VDC. Take your soldering iron, figure out the > GND and the +5VDC and you have comfortable power on the 1 amp range. As > always, PC switching power supplies are great too (just get a $5 DMM from > Harbour Freight and sacrifice its leads so you have a constant digital > power monitor....solder it on and wrap with electrical tape). > > What you do is you mount everything on your plywood. You take your > Fiscar's drill (with $2 high-speed steel Harbour Freight drill bits) and > you get a nice selection of dollar-store machine screws (and nuts) that > you've "tackle-box-ized". Shop the 99 Cent Store for these cheap tackle > boxes and pick up about a dozen of them to keep your stuff in (resisters, > relays, diods and voltage regulators). The trick with this is: mouser, but > listen...you can get premade kits for around $70 but they have less than $5 > worth of parts in them. What you want to do is put them together yourself > and when you get low on standard parts (like certain resistor values) you > just restock. All it takes is time to build these part kits, you put > together generic BOM (bill of materials) for your tackle box kits so you > have a nice selection of standard caps, diodes, transistors, MOSFETS, tiny > relays, optoisolators, MCU's like PIC's and of cource exotics like NEO6M's, > preprogrammed MCU's, and MCU6050's. > > Modern hacking requires attention to ESD (electrostatic discharge) because > a lot of your stuff has sensitive digital logic in it. The fix is basic. > Take a piece of silver solder and stick it in your ground power rail so > about an inch of its hanging out. Every time you get up to walk around > (where you accumulate chip-killing static) when you sit back down, just run > your finger unconsciously across the solder tail. You are now grounded. > Formal ESC with a wrist strap is ok too. But don't wire yourself to ground > btw as this can lead to you doing an impression of a light-emitting > resistor (an old joke but a good one); think about it electrically. > > OK, you BBB (in my case my BBBW), what you want to do is mount everything > to your plywood so when the wife says playtime is over, you can just put it > up. Also, claiming a second "junk drawer" in your kitchen is a life-saver > specifically for all your little tools and tackle boxes.What you do is you > get > > *** STANDOFFS *** > > To make standoffs you get a length of small-dimater ridged plastic tube > and you cut pieces off yourself (getting them from Home Hardware is > expensive) One of my little secrets. > > To attach your BBB to the plywood, mark the holes with a fine Sharpy, load > your bit in your Fiscars (at a slightly smaller diameter than the screw you > will use) and just sink a hole half-way through. Then take handful of > screws, a few standoffs and mount your BBB in a majestic location on your > plywood. Takes like 30 seconds and its secured for weeks of tinkering. > > Cut lengths of SOLID CORE insulated wire and strip the ends with a solid > professional grade wire stripper (they are cheap and so worth it). Now you > have all the wire you will ever need. First step with it is to wire your > breadboards power rails. Connect all the blue (or GND) rails with insulated > wire and what I do is run 3.3V on the left rail and 5V on the right rail > (because I'm working a lot of times with both BBB and TTL), but if just > working with 3.3V parts you can wire all your rails 3.3V to cut down on > confusion. > > You can do strain-relief by just knotting the power cord or whatever > through a hole in your plywood. Keeps you from jerking sensitive wires and > cables loose when moving around. > > THE PLAN > > OK, what you do is you experiment on your breadboards connecting > everything with wire. We all know how to do this. Get a complete working > version of the circuit(s) on your breadboard set up. This will become your > master reference for the next step: DIY PCB construction. > > > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/8563a592-2616-423c-a0aa-42f323f11ec5%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
