How to prototype? - Page 1
Forum section: electronics / beginners

author: audiotubes
author_rank: Regular Contributor
timestamp: May 23, 2023, 08:57:51 pm
content: Hi,I'm getting back into electronics very slowly after being away for decades. In the 1970s and 1980s I remember wire wrap was one of the more prominent ways to prototype. Is this still a good option?What else is there?I'm far from SMD, so just the ability to use discrete components and some ICs with sockets would be helpful.Thank you.

author: aeberbach
author_rank: Regular Contributor
timestamp: May 23, 2023, 09:04:06 pm
content: The big difference is now that now you have a choice of excellent and free PCB software packages, and PCBs are incredibly cheap. Wire wrap has advantages but is maybe not your main prototype method now.

author: artag
author_rank: Super Contributor
timestamp: May 23, 2023, 09:09:13 pm
content: I haven't used wire wrap for discrete components for a long time. It works well for IC packages (though wire-wrap sockets are expensive) but is a bit painful for passive components.I do, however, find it enormously useful for connecting together breakout boards. A great many small circuits are available on printed circuit with square-pin connectors and I often find I can prototype something by populating a small prototyping board (not stripboard but a matrix of plated holes) with a number of modules and wire-wrapping their connectors together. I can also create small circuits where needed by directly joining either through-hole or SMD components to the pads, then linking those sub-circuits to the wire-wrap pins.PCBs have dropped enormously in price. It's possible to make your own using the old techniques but really only practical for single-sided boards. However, complex 2 or more layer boards with plated through holes can be designed with free software and made for you in china or elsewhere for a few $ in a couple of weeks. The barrier to making a more complicated circuit on pcb is therefore now very low.

author: tggzzz
author_rank: Super Contributor
timestamp: May 23, 2023, 09:18:33 pm
content: Quote from: audiotubes on May 23, 2023, 08:57:51 pmSee arangeof good and poor techniques, plus some commercial products athttps://entertaininghacks.wordpress.com/2020/07/22/prototyping-circuits-easy-cheap-fast-reliable-techniques/Choose the rightcombinationfor your task!

author: TimFox
author_rank: Super Contributor
timestamp: May 23, 2023, 09:20:29 pm
content: If you are using through-hole parts and DIP sockets, there are sources for "protoboards", which are usually PC boards with similar patterns to solderless breadboards.Examples: a small onehttps://www.schmalztech.com/products/2-x-3-protoboardLarger one (double-sided with PTH also available):https://verotl.com/10-27563-3u-microboard-single-sided-development-pcb-with-grid-print

author: dobsonr741
author_rank: Frequent Contributor
timestamp: May 23, 2023, 09:56:38 pm
content: I suggest using solderless breadboards, to land and connect small breakout boards, and the occasional through-hole components. Though-hole is going out of reach every day, modern components never made. If you do not have a specific parts on protoboard it’s wort doing your own PCB sketchup and small OSH park run, you’ll get 3 pieces under a price of latte.As far as SMD, I’d think about getting into it, by buying a magnifying workstation, or whatever kind works for you. At least to plant a few parts on a breakout board.

author: tggzzz
author_rank: Super Contributor
timestamp: May 24, 2023, 07:41:38 am
content: Quote from: dobsonr741 on May 23, 2023, 09:56:38 pmI hate solderless breadboards with a vengence: you always end up spending more time debugging the breadboard than your circuit. When someone else asks me to help with their circuit, if it is on a solderless breadboard then I refuse. Why, and better alternatives at:https://entertaininghacks.wordpress.com/2020/07/22/prototyping-circuits-easy-cheap-fast-reliable-techniques/Other people seem to use them OK; I'm happy to let them get on with it!Apart from that, if you want PCBs with SMD and PTH components...Creating PCBs With Surface Mount Components. I have been creating circuits for mumble years, using wirewrap, IDC and standard PCB technology with plate-thru hole (PTH) components. I’ve recently been “forced” to use surface mount devices (SMD), and was concerned that it would be too difficult for an amateur using only equipment available at home.I was wrong; it was easy.https://entertaininghacks.wordpress.com/2015/03/25/creating-pcbs-with-surface-mount-components/Assembling PCBs With Surface Mount Components, Summary: it does work andisn’t too painful. Naturally I’m evolving methods and techniques as my skill improves.https://entertaininghacks.wordpress.com/2015/03/25/assembling-pcbs-with-surface-mount-components/Manufacturing PCBs With Surface Mount Components. Summary: cheap ‘n cheerful,good enoughfor double-sided experiments, butnot good enough for 4-layer impedance-controlled PCBs.https://entertaininghacks.wordpress.com/2015/03/25/manufacturing-pcbs-with-surface-mount-components/Homebrew PCB Reference Material. Articles that have helped me with the practical aspects of making PCBs at home.https://entertaininghacks.wordpress.com/library-2/homebrew-pcb-reference-material/

author: Solder_Junkie
author_rank: Frequent Contributor
timestamp: May 24, 2023, 07:11:30 pm
content: First off, run the proposed circuit in Spice modelling software, either LT Spice (free), or Tina (€49 - Student Version). The software is very good and avoids a lot of messing around soldering and swapping parts.While many of us were brought up on wire ended components (some even with valves), you have generally more choice, and less cost, with SMD parts, as nearly all modern electronic equipment uses SMD these days.As others mentioned, don’t be afraid of SMD. 1206, and perhaps 0805 sizes, can be hand soldered using a fine pointed soldering iron such as an Antex M12 (cheap around €25). No need for anything expensive. To see what you are doing, an Optiplex head magnifier is fine for these larger size parts. You need small diameter solder, typically 0.5mm or smaller.This excellent video shows how to hand solder SMD. A stereo microscope is needed for parts smaller than 0805. Unless you really need miniaturisation, try to stick with 1206 size resistors and capacitors and a head magnifier.https://youtu.be/eZtPR8_x0ncSJ

author: james_s
author_rank: Super Contributor
timestamp: May 24, 2023, 07:28:22 pm
content: Quote from: tggzzz on May 24, 2023, 07:41:38 amI don't know what you're doing wrong, but I've used solderless breadboards for decades and never really had any trouble with them. Like any tool or technique they have limitations, but as long as you understand these limitations and work within them they're fine.I also like Manhattan construction, particularly for anything involving RF. Perfboard is nice for low speed stuff that you want more permanent than a breadboard, and of course PCBs, but a lot of times for a one-off or something I'm not positive will work I don't want to go through the hassle and wait of making a board.

author: james_s
author_rank: Super Contributor
timestamp: May 24, 2023, 07:29:52 pm
content: Quote from: Solder_Junkie on May 24, 2023, 07:11:30 pmI routinely solder 0603 parts and SOIC chips with the same chisel tip I use for soldering through hole stuff. 1206 parts look gigantic to me now, and even SOIC is big enough to solder it onto perforated protoboards.

author: Nusa
author_rank: Super Contributor
timestamp: May 24, 2023, 07:43:49 pm
content: If you don't already have wire-wrap skills and at least a wrap/unwrap tool, I wouldn't suggest it in this day and age. That said, I still find occasional uses for it. Standard square header pins are close enough to wire-wrap ones that they work pretty well, at least for one wrap. I also have long headers, that I can get two or three wraps on. That said, you can run the same wires to solder points just about as fast.What kind of prototyping you need will depend on the complexity of your project. Simple learning exercises are the main place solderless breadboards are used. Also remember that you can turn most SMD chips into through-hole by using adapter boards with headers soldered to them. Many things aren't easy to find in DIP form anymore.

author: tggzzz
author_rank: Super Contributor
timestamp: May 24, 2023, 10:09:20 pm
content: Quote from: james_s on May 24, 2023, 07:28:22 pmBeginners don't understand the limitations; they don't even understand the circuit they are building!It is difficult to work around intermittent contacts (bent/dirty/unspringy spring contacts, dirty components), inductance in long flying leads, and capacitance between flying leads.You may get something that looks like it is working, but then someone bangs the table or sneezes, and something changes.

author: rstofer
author_rank: Super Contributor
timestamp: May 25, 2023, 05:07:39 pm
content: Since I started playing with FPGAs, I don't breadboard much logic. But when I did, I used an electric wirewrap gun. It was FAST!Like this:https://www.ebay.com/itm/364236003304SMDs (other than BGA and really fine pitch packages) are easy to hand solder. There are videos all over the Internet - Google for 'drag solder'Or, use a hot plate with a heat spreader (a 7" diameter saw blade) or convert a toaster oven. I have done them all and I think the hotplate is easiest. You can watch the solder flow.Some hot plates have a flat surface and the heat spreader isn't really required. Just put down dabs of solder paste, set the components and cook. Put the board on the hotplate, turn the temp to max and when the solder has flowed, use tweezers to pick up the PCB and set it on a hot pad. Turn off the hotplate. It's as easy as that!No, the temperature profile isn't even close to specified but we're not going to take the project to the Moon anyway.

author: Infraviolet
author_rank: Super Contributor
timestamp: May 25, 2023, 06:36:03 pm
content: My usual technique is to design and do initial proof-of-principle with through-hole parts on breadboards, then order a PCB (to which I'll solder SMD parts) for final designs. Where a part you want to prototype with is only available in SMD format you buy carrier boards to adapt it to rows of 2.54mm header pins which can slot in to breadboards, SMD-to-through-hole adapter boards are commonly sold for common SMD form factors and pin counts, and you can get custom ones fabricated very cheaply (JLCpcb and PCBway are two of the main cheap suppliers) if needed for strangely shaped parts.Extra notes:.. you'll need at a minimum a good lighted magnifier to solder SMD, a digital microscope is better still, vital if you're doing below 1.27mm pitches (or below 0603 passives)... you'll need sharp pointed conical soldering iron tips for SMD work, and getting THIN solder with a diameter of 0.3 to 0.4 mm is vital unless you're using a pasting setup (if you do a lot of SMD often it is definitely worth looking in to paste dispensing and oven-soldering).

author: james_s
author_rank: Super Contributor
timestamp: May 25, 2023, 08:32:00 pm
content: Quote from: tggzzz on May 24, 2023, 10:09:20 pmI've never had problems with intermittent contacts, I've pretty much always bought good quality breadboards though. Capacitance and inductance has never been an issue for the sort of hobby circuits I've built on breadboards. Stuff like LED blinkers, binary counters, mulivibrators, simple logic circuits, etc. Low frequency, simple circuits, I don't know, all I can say is the first circuits I ever built when I was a kid were on solderless breadboards and I still use them for quick prototyping and I can't recall ever having any sort of problems or difficulty, maybe I'm just incredibly lucky but they've always worked just fine for me.

author: james_s
author_rank: Super Contributor
timestamp: May 25, 2023, 08:34:34 pm
content: Quote from: rstofer on May 25, 2023, 05:07:39 pmI've always wanted to try building something with wire wrap, an 8 bit SBC or something like that but the damn sockets are so expensive these days it's hardly worth it. I do have a wire wrap tool and I use it sometimes to make connections to modules such as Arduino nano boards that have pins.

author: james_s
author_rank: Super Contributor
timestamp: May 25, 2023, 08:35:45 pm
content: For another take on prototyping, Elm Chan should be mentioned. His use of high density surface mount parts on protoboards is amazing.http://elm-chan.org/he_e.html

author: tggzzz
author_rank: Super Contributor
timestamp: May 25, 2023, 08:37:59 pm
content: Quote from: james_s on May 25, 2023, 08:32:00 pmDefine "low frequency" for digital circuits. If your reply is in terms of Hz, you lose.(Hint: transition time is the relevant metric)

author: tggzzz
author_rank: Super Contributor
timestamp: May 25, 2023, 08:40:11 pm
content: Quote from: james_s on May 25, 2023, 08:34:34 pmTrue.The wire can be cheap, though, and is superb for correcting mistakes on PCBs.

author: tychob
author_rank: Contributor
timestamp: May 25, 2023, 09:14:44 pm
content: Quote from: tggzzz on May 23, 2023, 09:18:33 pmMost of these examples seem to use through-hole or low pin count SMD devices. Are there any practical options other than breakout boards and custom PCBs for larger packages for digital signals with transition times on the order of 10-100ns? (74HCxx typical transition times)

author: tggzzz
author_rank: Super Contributor
timestamp: May 25, 2023, 10:16:03 pm
content: Quote from: tychob on May 25, 2023, 09:14:44 pmProvided leads are kept short and wide, Manhattan works well at UHF frequencies due to good ground plane. That's sufficient for, say, a 2ns transition time.As the pin count and connection complexity increases, custom PCBs are the only solution. Significant problem is ground bounce when large number of outputs change simultaneously.Have a look at the refs inhttps://entertaininghacks.wordpress.com/library-2/homebrew-pcb-reference-material/

author: tychob
author_rank: Contributor
timestamp: May 25, 2023, 10:41:48 pm
content: Quote from: tggzzz on May 25, 2023, 10:16:03 pmSo, to take a concrete example, the 74HC00. The largest surface mount package is a SOIC-14. With a gap between pins of 0.035". It has a maximum input transition rate of 139 ns/V at 4.5Vcc, or roughly ~600ns maximum transition time. Output transition time of a 15pF load is 7ns typical. This seems to be about as basic an introductory IC as you can get. Would you suggest an alternative for digital logic?Are you proposing that a beginner should start by soldering wires of less than 0.015" with that spacing without shorts? And that those shorts will be less common than reliability issues from bad connections on a breadboard? Or are you saying that prototyping is only doable with the most basic passives, and we might as well just use discrete transistor TTL with us switching times?The 74HC00 is one of the most basic ICs out there for digital logic. If thats impractical to experiment with, thats a huge barrier to even consider electronics as a hobby. Perhaps we just just play in simulators and ignore that the physical world exists.For someone who has yet to master 0.1" soldering precision, and actually wants to have physical interaction with surface mount MSI, rats nest and manhatten seem from the outside like the have worse tradeoffs in terms of needing to master reliable precision soldering vs breadboards which whilst unreliable, are manageably unreliable, or where available DIP + protoboard.This is the one characteristic where the LM741 shines: With a maximum skew rate of 0.5V per microsecond, it is a low speed part.

author: tggzzz
author_rank: Super Contributor
timestamp: May 25, 2023, 11:26:23 pm
content: What do you want me to say? I can't change physics!Do the next calculation: the current required to charge the capacitance, assume wires having 1nH/mm inductance, and the voltage induced in the PSU wire's inductance by that current change.Look at the pictures to see examples of how people have addressed the issues.

author: tychob
author_rank: Contributor
timestamp: May 26, 2023, 12:43:11 am
content: This is a die design, that has been used for decades, in DIP packages, in setups with far worse electrical characteristics. Breadboards, protoboards, single and two layer PCBs. How did this die work, when used in a DIP-14 package? Yet when put in a SOIC-14 package it no longer works in any of these environments? How does changing the plastic effect it so drastically?

author: rstofer
author_rank: Super Contributor
timestamp: May 26, 2023, 01:25:41 am
content: Quote from: james_s on May 25, 2023, 08:34:34 pmThe Ben Eater 6502 project should be easily achieved:https://eater.net/6502

author: tychob
author_rank: Contributor
timestamp: May 26, 2023, 01:31:05 am
content: Quote from: rstofer on May 26, 2023, 01:25:41 amOnly if you can make a 74HC00 work on a breadboard, which apparently is too fast for breadboards.(The Ben Eater design uses a 74HC00 for address decoding)

author: dobsonr741
author_rank: Frequent Contributor
timestamp: May 26, 2023, 02:37:51 am
content: QuoteAgreed. I just did a TPL0102 breakout board soldering in 10 minutes. Most of the time was the heating up of my hotplate. The QFN pitch is 0.4mm.

author: thermistor-guy
author_rank: Frequent Contributor
timestamp: May 26, 2023, 04:47:06 am
content: Quote from: audiotubes on May 23, 2023, 08:57:51 pmI still use wire-wrap, for prototyping some automated, low-frequency test setups.I have test jigs with connectors fastened to light steel sheet with custom cutouts, no pcb. Wire-wrap wireconnects the connectors on the back of the sheet. This is Mil. spec wire from many years ago. Twisted ribbonIDC and other cables plug into the top side. I use the same steel sheet to make cheap connector shells.The jigs connect test equipment, like a DVM+scanner, to components and circuits under test.One of my current projects is a DIY temperature chamber, for measuring/screening components over a temperaturerange. Some of that will use wire-wrap construction.

author: Solder_Junkie
author_rank: Frequent Contributor
timestamp: May 26, 2023, 05:16:25 am
content: This thread has gone off on a tangent, and the original poster hasn’t given any input beyond the initial question posed.The OP is returning to electronics after around 40 years, in other threads he (assuming that is their gender) asks about meter leads and scope probes, plus feeding 2 amps from one preamp. The likelihood is that he is mostly interested in audio, or perhaps basic switching circuits, that were commonly around in magazines of that era.My original reply suggested using Spice modelling, which wasn’t in use by constructors working on their kitchen table back then, plus to consider the larger size SMD parts due to lower cost compared to wire ended. Although SMD really involves making print boards, either laser printer/heat transfer paper/ferric chloride etching, or sending the layout to China.As a “home brewer” who started out in the 1970s, I have progressed to Spice modelling and having boards made by JLC PCB, but I don’t go near high speed logic, or FPGA devices. I guess such talk has put off the OP responding…SJ

author: tggzzz
author_rank: Super Contributor
timestamp: May 26, 2023, 08:39:05 am
content: Quote from: tychob on May 26, 2023, 12:43:11 amAbsence of evidence is not evidence of absence. In this case, therewere manyproblems.There were a lot of problems with TTL logic designs in thelate 70s, because designers didn't yet know how to layout decent power supply tracks to the ICs. Although they were experienced analogue engineers, they were beginners (relevant!) at logic design, and laid out the Vcc and Gnd tracks on 2-sided PCBs the way they did analogue circuits. I remember such people being amazed that the first logic design (with maybe 100 ICs) from our company division layed out on a double-sided PCB worked correctly first time. My magic technique? Layout a grid Vcc and Gnd and 0.1µF decouplers first, only then start laying out signal tracks.There were a lot of subtle intermittent problems with the faster logic families that appeared in themid 80s, when all 8 outputs switched simultaneously. They looked OK on the bench, but gained a reputation for problems in the field. Eventually traced to ground bounce.So, you are too optimistic.

author: artag
author_rank: Super Contributor
timestamp: May 26, 2023, 09:00:04 am
content: > So, you are too optimistic.I have an old Racal counter/timer built with 7400 series logic and a Nixie display. It has no decoupling capacitors - not something anyone would do today!It actually has a fault but presumably mostly worked when in production.I remember being told at college (via Ivor Catt's book on hardware design) that the reason this kind of design kinda worked is that the transient supply currents taken when all the dividers switched resulted in a reduced voltage on the 5V rail, and therefore an overall reduction in current consumption which helped maintain the shortfall.Hardly a design technique you'd want to rely on but an explanation of why dodgy old designs apparently worked, before people understood the failure mechanisms and mostly had these circuits working by luck and experiment.

author: tggzzz
author_rank: Super Contributor
timestamp: May 26, 2023, 09:41:34 am
content: Quote from: artag on May 26, 2023, 09:00:04 amA lot depended on thetypeof TTL logic, how many outputs it has, and what it was driving. TTL, LTTL, HTTL weren't too bad, STTL was worse, LSTTL better, FTTL could be poor. The early 14/16 pin DIPs typically had 4 (maybe 6) outputs, later 24 pin DIPs had 8 and were driving 100ohm bus lines.I have 74LVC1G14 devices driving 150ohms in 300ps.https://www.eevblog.com/forum/testgear/show-us-your-square-wave/msg1902941/#msg1902941

author: tychob
author_rank: Contributor
timestamp: May 26, 2023, 10:47:46 am
content: So for the beginner, my understanding is there is no option that will be reliable. Its a matter of trading off subtle ground bounce issues, which probably won't cause you too many issues, pin shorts from inability precisely solder yet (can't drag or reflow when dead-bugging), breakout boards that add up in cost and trace length (reflection issues, decoupling inductance etc), or having to work with PCBs that are for a subtly wrong circuit because you made a schematic error and don't want to wait 2 weeks for another replacement PCB. Is this an inaccurate summary?Can you recommend any breakout boards that allow placing decoupling capacitors with less inductance than typical placement on a perfboard?, most designs seem not to include them resulting in a larger loop area.I suppose the reliable workflow is to design a custom PCB, discover its wrong, wait 2 weeks, and repeat until you get the PCB right. Which is such an encouraging workflow for beginners compared to occasional unreliability?Or for the beginner who is flush with cash, you could just spend hundreds on expedited shipping for PCBs with mistakes in them.

author: tggzzz
author_rank: Super Contributor
timestamp: May 26, 2023, 12:35:32 pm
content: Quote from: tychob on May 26, 2023, 10:47:46 amBefore stating "subtle" and "won't cause you too many issues", follow my suggestion anddo the calculation. I've done it elsewhere; now demonstrate you can do it too: how many mV of ground bounce would you expect to see (hint: not single digits).QuoteIt appears to be a deliberate strawman argument. Not impressive.Read the refs I gave. Note that breakout boards on fleabay are so cheap you can keep them in stock. Note especially the statements therein:...This professional example shows you can combine whichever techniques are appropriate......The techniques can be mixed and matched wherever convenient......use whichever techniques you like...QuoteIf that is what you are determined to read and understand, then I am not going to be able to dissuade you.Most people will read with a more open mind and will make their own nuanced decisions based on the physics, their capabilities, and their use cases.

author: tychob
author_rank: Contributor
timestamp: May 26, 2023, 03:18:59 pm
content: Quote from: tggzzz on May 26, 2023, 12:35:32 pmI don't care what the theory says. I care about the body of examples (including the extremely famous Ben eater project), of these systems apparently working well enough in practice. Perhaps you could set up a physical experiment showing how often this results in glitches at the output? Alternatively, could you point me to where on the 74xx datasheet it specifies what that ground bounce number means in terms of output voltage? Because on a 5V signal, I don't see any reason to care about hundreds of mV. Its not whether the ground bounce is happening, its whether that effects the logical properties of the system on a frequent enough basis. Can we quantify this in terms of bitflips for some circuit?Quote from: tggzzz on May 26, 2023, 08:39:05 amAnd this is all I am looking for in terms ofGood Enough. These are circuits that will never leave the bench, and if you could quantify what you mean by faster logic families, then as much as possible I will try to avoid them. (I already avoid 74AC and 74AHC for this reason).The biggest issue I have with breakout boards: Most of the chips I work with are also available in DIP form still, and as far as I can tell, in all the properties you talked about, an SMD chip on a breakout board is inferior to a DIP equivalent. So why not just use the DIPs. There is a separate question about deadbugging vs perfboard for DIPs, but every thing you list seems to be a reason to stay with DIPs, since its a lot easier and shorter to wire a leaded capacitor between the two pins of a DIP on the opposite side, than to put a decoupling capacitor anywhere near the power pin on a standard breakout.Quote from: tggzzz on May 26, 2023, 12:35:32 pmAll of the techniques listed that I could see are based on one of two things: Precision mechanical fabrication, whether thats footprints or soldering. Or bringing the small pitches out to larger pitches that they are actually workable, losing most if not all the benefits of SMD components. If anything, what I feel I've learned from it is the best option looks to still be dead-bugged DIPs and through hole on a copper sheet, and stock up on DIPs whilst they are still available. And use breakouts as a substitute for DIPs where the manufacturer no longer offers them.

author: tggzzz
author_rank: Super Contributor
timestamp: May 26, 2023, 05:23:17 pm
content: Quote from: tychob on May 26, 2023, 03:18:59 pmSo, your mind is fixed, and won't be swayed by the theory and practice that has been known fordecades. Not worth my wasting my time trying to change a fixed mind.You remind me of the professionals that denied metastability existed and was a problem, because they hadn't observed it themselves - often because they hadn't looked carefully enough.Back in the days with slow logic (e.g. LSTTL being new), things like Rogers Micro-Q capacitors were available for retrofitting to try to reduce problems found after layout:http://www.farnell.com/datasheets/22715.pdf. Alternatively there were also ic sockets with built-in capacitors, but they could never be as good. They would be useful for your use case, but I doubt they can be obtained any more.QuoteIf you think datasheets tell you everything, then can I interest you in this bridge I have to sell?You need to look at application notes, be aware of industry standard practice, and be willing to learn from mistakes made by and lessons learned by other people.QuoteIfeaseis more important than reliability, why don't you omit the decoupling capacitors? After all, your circuit will probably still work most of the time.Here's an example of a double-sided board with a decoupling capacitor right next to each of the 74LVC1G14 SOT-23 packages. Despite each package containing only one output (vs the 4-8 in the packages you are suggesting), I found the circuit improved when I added that extra decoupling capacitor on top of the component.To improve decoupling, I'm considering re-spinning the board as a four layer board where there is a full Vcc and Gnd plane separated only by the prepreg thickness.QuoteUse whatworksfor you, if you can get the DIP components and it suits your uses. Do keep as complete a ground plane as possible, and make sure the Vcc (etc) doesn't meander more than necessary.

author: james_s
author_rank: Super Contributor
timestamp: May 26, 2023, 07:34:09 pm
content: Quote from: tggzzz on May 26, 2023, 05:23:17 pmLikewise, your mind is fixed and won't be swayed by the fact that millions of hobbyists manage to build working circuits on solderless breadboards and have for many decades without the numerous difficulties that you insist are inevitable. We're talking hobby circuits here, not critical life safety production hardware. I don't know what to tell you, other than I've built countless circuits on breadboards over decades and I've never experienced any of these problems you claim are all but guaranteed to occur. In the real world most stuff is pretty tolerant of less than ideal conditions. I have breadboarded even some fairly high speed stuff, PWM oscillator that ran at tens of kHz, microcontrollers with SPI and I2C buses, and at one point all but the final output stage of a ~600W resonant SMPS powering a dental xray head. Definitely not the preferred technique for that but it worked none the less. I kind of suspect you have never even really tried using a solderless breadboard and simply looked at one and thought "that will never work" or maybe tried a cheap worn out one 30 years ago, had some issues and made up your mind that they were all like that. I don't know what else it could be. They work fine for the rest of us.

author: james_s
author_rank: Super Contributor
timestamp: May 26, 2023, 07:49:16 pm
content: Quote from: tggzzz on May 25, 2023, 08:37:59 pmYes, you've stated this on numerous occasions, I'm sure you think it makes you sound very smart.Transition time is just not that important for a lot of stuff. An LED blinker or audio oscillator doesn't care about transition time, microcontroller IO like reading buttons and pots, again irrelevant, even digital stuff like SPI is surprisingly tolerant of slop as long as you don't try to clock it too high. Hobbyists build stuff all the time that works, despite absolutely horrid construction techniques.

author: tggzzz
author_rank: Super Contributor
timestamp: May 26, 2023, 08:09:23 pm
content: Quote from: james_s on May 26, 2023, 07:49:16 pmtsetupand tholdhave to be met whether the clock rate is 1Hz or 1GHz.Ditto voltage/current transients causing glitches and false clocking.

author: Infraviolet
author_rank: Super Contributor
timestamp: May 26, 2023, 08:42:21 pm
content: Reply #32:"Can you recommend any breakout boards that allow placing decoupling capacitors with less inductance than typical placement on a perfboard?"This is where you design them for yourself, just find a footprint in your preferred PCB design package that matches the chip of interest, and add in some traces leading to a few 0603 SMD capacitor footprints between the power pins. You can put in several such combinations,so a single design of breakout board could accomdate for decoupling caps between multiple different pin pairs (to account for when different chips have power pins in different places). You can order a batch of 5 such boards (min quantity) from one of the cheap PCB suppliers for <£3 to arrive in a bit under 2 weeks (perhaps £10 shipping), or many more copies of the board for not much shipping increase. Then you've got a stock of breakout boards with spaces where you can solder a decoupling cap where you need it and leave the other spots (or diferent power pin arrangments) for decoupling caps empty.Deadbugging is something I'd pretty much never recommend, particularly not to a beginner, getting a decent solder joint between things which aren't initialy rigidly mechanically held is tough.Another trick for faster workflow is to put lots of spaces on a pcb design for zero ohm 0603 resistors to jump between different traces, even those which wouldn't usually be expected to be connected. I've never felt a need to do this, and the schematic view would be hideous, but this method wouldlet you make a board which you could easily adapt by soldering in new zero ohm jumper resistors where necessary to correct for any mistakes in your initial design and breaking traces elsewhere with a blade or sharp edge.I wouldn't worry too much about trace lengths and typical trace inductances, you have to be doing RF type frequencies before this matters, you can get away with ignoring this sort of thing at frequencies right up to several MHz. I've done tests on breadboard of things at 100s of KHz with no issues at all, the breadboard wires make it vulnerable to knocks which can loosen a connection, but one only uses a breadboard to check a schematic works before ordering a PCB which gives a far more reliable physical construction when one has the confidence in the design principles which breadboarding the schematic will have given you."I suppose the reliable workflow is to design a custom PCB, discover its wrong, wait 2 weeks..."The ONLY time I ever ended up buying a PCB that was badly wrong in the described fashion was when I ordered one without first checking on breadboard the principles inherent in each subsystem* of the board. Every other time the board I've ordered has either worked tolerably first time, perhaps with some optimisation desired for a second revision, or has needed no more changes than substituing the value of passives in a few places differently to what I expected and had printed on the silkscreen.*useful hint, if breadboarding the whole of a complex circuit (robot motherboard) at once is too much you can breadboard just each logically separate subsystem (ultrasound prixmity sensor, motor drivers and encoder reading on a per motor basis, battery monitoring and voltage regulation,infrared data receiving...) one at a time and then combine these individual and logically separate schematics on the one final board design.

author: tychob
author_rank: Contributor
timestamp: May 26, 2023, 09:48:51 pm
content: Quote from: Infraviolet on May 26, 2023, 08:42:21 pmFor complex chips that really need the decoupling, this is workable, but does increase the design cost as this is now an extra step in the workflow as soon as you step outside an existing convention.Quote from: Infraviolet on May 26, 2023, 08:42:21 pmThis was sort of what I was trying to get at, especially at smaller pitches used in SMD devices. Yet the choice seems to be: Ground plane, Trace length/inductance or turnaround time, you can pick any 2. Unless you start making your own PCBs.Quote from: Infraviolet on May 26, 2023, 08:42:21 pmIts hard to know where to put these. The ben eater design has over 200 pins for example. Putting a resistor on everything seems like it would get messy.Quote from: Infraviolet on May 26, 2023, 08:42:21 pm7-600ns. Straight of the datasheet. Thats an FMax of roughly 800Mhz, when running at the absolute slowest. But this is exactly what I meant by the body of examples of works well enough for the bench. It would be nice if tggzz could provide some examples in terms of system level impact of something failing.Quote from: Infraviolet on May 26, 2023, 08:42:21 pmThis was a retorical response about the earlier comments of how breadboards are unreliable. You're right that workflow is only applicable if you don't breadboard. But if you are that dogmatic about not using breadboards as the poster was, and don't have the soldering skills for deadbug, what methods you have for prototyping vs just hoping the PCB works. It was about how if don't try and work with the limitations of breadboards, you end up in other limitations elsewhere.

author: tggzzz
author_rank: Super Contributor
timestamp: May 26, 2023, 10:17:59 pm
content: Doing X is all about developing expertise and skills relevant to X.Soldering is pretty fundamental to all electronics beyond plugging somebody else's modules together. So develop soldering skills ASAP. There are many benefits, no downsides, and no reason not to.Don't use lack of soldering skills as an excuse; do use it as a trigger for self development - and having fun making mistakes while learning.

author: julian1
author_rank: Frequent Contributor
timestamp: May 26, 2023, 10:24:16 pm
content: QuoteIt's all a tradeoff as you suggest. You can debate where the boundaries are, and these will change per project.For simple, slower circuits - prototype with solderless breadboards/breakouts. Or solderable breadboards for better/more robust/permanent connections.For discrete digital, you can probably slow/relax the clock/ for test/ debugging/ timing analysis anyway.QuoteFor fast or complicated, use pcbs with gnd planes, then follow best-practice or datasheet layout advice/guidelines which will assume a pcb, and which will vary with need and component choice.So 74hc get a decoupling cap at the supply pin. while a bga gets an assortment of backside caps, for every power pin, and the range of supply voltages.There's no need to aim for a perfect pcb. It's a lot easier to bodge a SMD pcb with the decoupling in place, and which is close to working, than it is to work up something from scratch.So turn-around time for pcb manufacture and shipping is frustrating, but the number of design revisions may be fewer.At some point switching to pcbs is natural anyway - because it is easier to rely on the schematic as the authoritative source for the circuit, and use source control to manage change.Trying to reverse-engineer a half-forgotten and bodged together board back into a source schematic with comments and design justifications, has its own overhead.The Ben Eater stuff is very far from optimum for a speedy design workflow.Instead he explores what happens, when you take a technology choice and push it in a particular direction.

author: tychob
author_rank: Contributor
timestamp: May 26, 2023, 10:30:44 pm
content: Quote from: tggzzz on May 26, 2023, 10:17:59 pmThere is soldering and soldering. Soldering 0.01" wire precisely within 0.02" is a much harder place to start than soldering 0.03" to within 0.1". I'm not saying it isn't a reasonable end goal, I'm saying its an unreasonable expectation at the start. This is why I come back to DIPs and reflow. DIPs need a lot less precision before you can get started. Which is just meaningless grind until you manage to actually succeed. The standard argument regarding SMD soldering is its not any harder because you can use techniques like drag or reflow. Which don't apply to deadbug, meaning it is significantly harder. In deadbug you are treating the package like a very small pitch DIP. Do you not agree that 0.02" is significantly more precise than 0.1"? That is straight theory.

author: tggzzz
author_rank: Super Contributor
timestamp: May 26, 2023, 10:54:22 pm
content: Quote from: julian1 on May 26, 2023, 10:24:16 pmtholdrequirements are unchangedwhateverthe clock frequency.Power supply glitches and ground bounce won't be improved by having a lower clock frequency. Their effects occur a fixed time before and/or after a clock, whenever that clock happens. Yes, a 1ns problem will cause just the same problems with a 1Hz clock as with a 100MHz clock.Apart from that, you make sensible points that i agree with.As for Ben Eater, his "about" page indicates zero electronics training. It looks like he is a typical software engineer that is playing around with "digital" circuits and signals -without realising they are actually analogue circuits and waveformsthat are beinginterpretedas digital signals.As for the "I've done X and not had problems (so you can too)" type of statement you often see... They are as unimpressive as "I've run into the road without looking and not been knocked over (so you can too)". Absence of evidence of bad effects is not evidence of absence of bad effects.

author: Jwillis
author_rank: Super Contributor
timestamp: May 27, 2023, 02:43:34 am
content: I don't think theirs a Holy Grail to prototyping. Each method has its merits as well its faults. I have adopted all methods available based on availability of items, complexity of the circuit , and the type of circuit I'm working on .I agree with tggzzz in the point that bread boards can be a real pain in the backside for trouble shooting a problem that wasn't there a hour a go. Specifically when the circuit starts to get really complex. In my short experience I found is to keep bread boarding simple and once that small part of the larger circuit works put it on something more permanent like a protoboard. Theirs nothing in the rules that says you can't connect individual protoboards together by wire wrapping or stacking.Somethings you might have to insert another circuit or component so why not just dead bug it in.I've even used the neutral bus bars from an electrical panel for high current power rails. Sometimes you just have to take the unorthodox path and make things up as you go.Basically I'm just saying is you can't be a zealot. That just limits your options.

author: tychob
author_rank: Contributor
timestamp: May 27, 2023, 03:02:55 am
content: Quote from: Jwillis on May 27, 2023, 02:43:34 amWhat sort of protoboard did you use to provide a ground plane, or did you skip that? My understanding was that perfboard didn't have a solid ground plane.

author: TimFox
author_rank: Super Contributor
timestamp: May 27, 2023, 03:32:24 am
content: Quote from: tychob on May 27, 2023, 03:02:55 amI have used expensive protoboards from Vero that had a "collander" ground plane covering each of the top and bottom layers.

author: thermistor-guy
author_rank: Frequent Contributor
timestamp: May 27, 2023, 04:03:26 am
content: Quote from: TimFox on May 27, 2023, 03:32:24 amI have Vector-brand protoboards of this time.To the OP: wire-wrap can work and is useful, in some situations, I gave an application where it is my go-to build technique.More generally, I suggest you think in terms of capability and craft. You want the capability to prototype the projects you want,in a style that suits them. That might be through-hole, or SMD, or a mix, depending on the project.Ideally you want to have the tools, components, and the skills for a variety of prototyping styles, so you are free to pick and choose.And craft - any style can be used well or badly, so work on honing your technique, whatever styles you work with.

author: Nusa
author_rank: Super Contributor
timestamp: May 27, 2023, 04:51:49 am
content: Quote from: tychob on May 26, 2023, 10:30:44 pmGeez, at least use the correct numbers. 0.1" is thepitchof DIP, while 0.05" is thepitchof SOIC-14. The actual width of pins on both packages isabout the same, although the lengths are different. And you can use the same size wire in both cases, so that's not a factor.But the bigger question is why are you putting so much effort into finding obstacles instead of doing and learning? If you only want to use DIPs for now, that's fine.

author: EPAIII
author_rank: Super Contributor
timestamp: May 27, 2023, 06:14:41 am
content: Key words here: "...for your task."Quote from: TimFox on May 23, 2023, 09:20:29 pm

author: Jwillis
author_rank: Super Contributor
timestamp: May 27, 2023, 06:39:40 am
content: Quote from: tychob on May 27, 2023, 03:02:55 amI just use standard protoboards and if I need a wider, thicker trace or a ground plane I have copper foil and copper sheet I can cut into any shape I want and solder it onto the board.I often cut copper sheet to build up traces when required.

author: tggzzz
author_rank: Super Contributor
timestamp: May 27, 2023, 08:26:24 am
content: Quote from: tychob on May 27, 2023, 03:02:55 amI gave an example in my references, plus the reasons why I like it. Works well for SMD components and PTH.

author: tggzzz
author_rank: Super Contributor
timestamp: May 27, 2023, 08:27:45 am
content: Quote from: Nusa on May 27, 2023, 04:51:49 amExactly.

author: tggzzz
author_rank: Super Contributor
timestamp: May 27, 2023, 08:40:49 am
content: Quote from: TimFox on May 23, 2023, 09:20:29 pmI like these “uncommitted manhattan” BusBoard PCB where the pads are not connected to full ground plane – you add jumpers to the ground plane where convenient.http://www.busboard.com/surfacemountpcbs.Acceptable price, and you can chop them up for small circuits.Many other patterns available on the site, including similar patterns to solderless breadboards, e.g.http://www.busboard.com/pcbbreadboards

author: Infraviolet
author_rank: Super Contributor
timestamp: May 28, 2023, 04:08:11 pm
content: "Trying to reverse-engineer a half-forgotten and bodged together board"Useful tip, always have pen and paper beside you when breadboarding, draw the schematic of what you're about to build before you build it, and edit the schematic if you make changes to it as you build/refine. Then you've got a paper schematic to copy from when you create the schematic for the PCBs.

author: audiotubes
author_rank: Regular Contributor
timestamp: May 28, 2023, 06:13:28 pm
content: Quote from: Solder_Junkie on May 26, 2023, 05:16:25 amYes, that's right.I have always been into audio and have done general through hole repairs and built some basic power supplies and done a few kits. But it's clear I'm 40 years behind you guys. And I cannot even remember what I used to know.I'm going to read the Forrest Mims books again and start with real simple projects on a breadboard. If I can get anything to work, it will be a thrill.Although I don't understand much of what was written, I'm reading the posts when I can.Thanks all

author: tggzzz
author_rank: Super Contributor
timestamp: May 28, 2023, 09:12:08 pm
content: Don't be afraid of new and/or small things (they aren't as bad as you fear).Do be aware of what you might encounter, what's out there to help overcome problems (as mentioned in this thread).Have fun, and makenewmistakes