What is the best way to test a circuit design with surface mount parts? - Page 1
Forum section: electronics / testgear

author: Ben321
author_rank: Frequent Contributor
timestamp: October 13, 2022, 08:09:56 am
content: Protoboards have holes in them for through-hole components. Unfortunately many components nowadays are ONLY available as surface mount, meaning you really can't test your circuit on protoboard if any of the components in the circuit are only available as surface mount components, unfortunately. It would be nice if there was some kind of surface mount to pins adapter that would let you attach a surface mount component to a protoboard, but I don't see how such an adapter could be made.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: October 13, 2022, 08:12:53 am
content: google surface mount to dip socket1st result,https://abra-electronics.com/interconnects/sockets/surface-mount-to-dip/

author: Ben321
author_rank: Frequent Contributor
timestamp: October 13, 2022, 08:34:50 am
content: Quote from: Ed.Kloonk on October 13, 2022, 08:12:53 amThat's cool. I didn't even know such existed.

author: Fungus
author_rank: Super Contributor
timestamp: October 13, 2022, 10:01:56 am
content: You can buy them by the hundred in Aliexpress:https://www.aliexpress.com/wholesale?SearchText=smd+pcb

author: Ben321
author_rank: Frequent Contributor
timestamp: October 13, 2022, 10:04:24 am
content: Quote from: Fungus on October 13, 2022, 10:01:56 amThat site just sells cheap Chinese junk. I'd prefer major electronic component distributors like Mouser or Digikey.

author: Fungus
author_rank: Super Contributor
timestamp: October 13, 2022, 10:08:24 am
content: Quote from: Ben321 on October 13, 2022, 10:04:24 amThe ones on mouser/digikey are probably made in the same factory, they just have more middlemen.

author: Ben321
author_rank: Frequent Contributor
timestamp: October 13, 2022, 10:27:28 am
content: Quote from: Fungus on October 13, 2022, 10:08:24 amStuff you see on Alibaba doesn't even say what company made it. At least on the sites I listed it says the name of the manufacturer. Also I think that Mouser and Digikey are direct distributors for most electronics manufacturers. They buy products from the manufacturer, then sell to the consumer. Same as Alibaba. Except with Alibaba you don't know if it's a legit company, or some no-name shady business selling it through Alibaba on behalf of the real manufacturer, concealing the identity of the manufacturer.

author: tggzzz
author_rank: Super Contributor
timestamp: October 13, 2022, 10:39:12 am
content: Quote from: Ben321 on October 13, 2022, 08:09:56 amin addition to the breakout boards mentioned by others, some alternative construction techniques and components are illustrated and discussed athttps://entertaininghacks.wordpress.com/2020/07/22/prototyping-circuits-easy-cheap-fast-reliable-techniques/I encourage people not to be dogmatic about construction techniques but to choose the bestcombinationof techniques for thespecific circuitbeing prototyped. excepetion: avoid solderless breadboards, unless you want to spend more time debugging the implementation than debugging your circuit.

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 13, 2022, 10:51:05 am
content: i made my own. when i made several small pcb circuits to send to cheap junk pcb manufacturer, i have more room in the 10cm x 10cm board, so i "hitch hike" the adapters in. so i will get 10-20pcs basically for free. shown in picture (circled in red) a few that i usually work with, sot23-3, sot6 and soic8 to dip8.. if you dont trust cheap junk seller/manufacturer, you can diy and send to not cheap junk, or just get from your trusted digikey at $3+ per piece...https://www.digikey.com/en/products/filter/adapter-breakout-boards/643

author: Fungus
author_rank: Super Contributor
timestamp: October 13, 2022, 10:51:53 am
content: Quote from: Ben321 on October 13, 2022, 10:27:28 amI'm not exactly sure how a PCB can be "shady", but let's do the math:I can buy one adapter from the site you posted for $1.33 plus about $20 shipping:https://abra-electronics.com/boards/surface-mount-to-dip-adapter-boards/bob-00717-sot23-to-dip-adpater-bob-00717.htmlOr... I can buy 50 adapters from Aliexpress for less money and under $2 shipping:https://www.aliexpress.com/item/3256802590742527.htmlYour choice.

author: pcprogrammer
author_rank: Super Contributor
timestamp: October 13, 2022, 10:55:13 am
content: Quote from: Ben321 on October 13, 2022, 10:27:28 amWhy pay more for it then needed when it is just a simple pcb without components on them. Order a bunch for each size and you are basically set for life. Even if the quality is a bit sub par, which to my experience it is not, as long as only used in prototyping it does not matter. But hey, it is your money

author: Fungus
author_rank: Super Contributor
timestamp: October 13, 2022, 11:05:19 am
content: Quote from: pcprogrammer on October 13, 2022, 10:55:13 amNor mine.

author: nctnico
author_rank: Super Contributor
timestamp: October 13, 2022, 12:46:55 pm
content: Quote from: Fungus on October 13, 2022, 10:08:24 amTypically the self branded stuff from distributors is worse in quality compared to what you buy from Aliexpress or Ebay.Where it comes to prototyping smd parts: use veroboard and solder components on the solder side and/or mount chips dead bug style. If you can wait a bit just make a board that has some flexibility for experimenting. Much more reliable than using any breadboard solution

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 13, 2022, 02:01:10 pm
content: Quote from: nctnico on October 13, 2022, 12:46:55 pmwhat is more flexible than a breadboard?

author: Fungus
author_rank: Super Contributor
timestamp: October 13, 2022, 03:32:46 pm
content: Quote from: Mechatrommer on October 13, 2022, 02:01:10 pmhttps://www.aliexpress.com/item/32916867562.html

author: Fungus
author_rank: Super Contributor
timestamp: October 13, 2022, 03:37:55 pm
content: Quote from: nctnico on October 13, 2022, 12:46:55 pmOr buy one on Aliexpress.https://www.aliexpress.com/item/32595260722.html

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 13, 2022, 03:50:40 pm
content: Quote from: Fungus on October 13, 2022, 03:32:46 pmi assume you are joking(flexible is in term how easy we change circuit without solder/desoldering hazard.)

author: artag
author_rank: Super Contributor
timestamp: October 13, 2022, 03:56:12 pm
content: The hole-matrix boards are fine for SMD prototyping. Just treat the matrix as a matrixof pads, and solder up to 4 SMD components to each pad. The gaps between pads are typically 0.5mm so a range of SMD footprints will fit, including SOT-23.You can use the holes for linking the pads on the other side with wire, if needed.ICs are more of a problem. The breakouts mentioned above help, or small (less than 8 pin) components may fit directly.I'm not so keen on the boards with a selection of SMD footprints - it's hard to use more than one or two of them. Small generic areas with a 50 thou or 20 thou grid of pads would be useful.

author: pcprogrammer
author_rank: Super Contributor
timestamp: October 13, 2022, 04:01:13 pm
content: Quote from: Mechatrommer on October 13, 2022, 03:50:40 pmBut both tggzzz and nctnico were writing aboutreliabilitywhich is gained by using solder. Solder-less breadboards are good for many hours of debugging your design due to improper connections.

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 13, 2022, 04:36:57 pm
content: Quote from: pcprogrammer on October 13, 2022, 04:01:13 pmwhat prohibits you from making improper (wrong) connection on perfboard? none! make sure the breadboard and jumper pins are clean and know its limitation (not for power connection and inductive/capacitive sensitive circuitry) btw i have both bread and perf board in stock, i use which one more suitable. if i need very quick verification, breadboard is the one i grab.

author: tggzzz
author_rank: Super Contributor
timestamp: October 13, 2022, 04:54:09 pm
content: Quote from: pcprogrammer on October 13, 2022, 04:01:13 pm... don't forget the wonders of ground bounce when, given long inductive wire connections, "too many" outputs simultaneously change. There's nothing like an intermittent pattern-sensitive fault to hone your debugging skillsDitto loosely coupled mutual inductors forming a transformerDitto capacitors forming new and challenging feedback loops. example from a Tektronix 184. At least Tek included the inductors in the schematic; the horseshoe is L70, the wire hoop partially hidden behind it is L69, and their mutual inductance forms a transformer

author: nctnico
author_rank: Super Contributor
timestamp: October 13, 2022, 05:51:21 pm
content: Quote from: Mechatrommer on October 13, 2022, 04:36:57 pmFor quick verification I use a simulator.

author: tautech
author_rank: Super Contributor
timestamp: October 13, 2022, 06:33:23 pm
content: Quote from: Ben321 on October 13, 2022, 10:27:28 amIt seems you have lost your roadmap so let's put you straight.Alibaba = business to business contact portal.AliExpress = retail Alibaba portal used by sole traders and some business too. Equivalent to eBay that also sell some cheap Chinese junk.A little less of your incessant China bashing please.

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 13, 2022, 06:51:19 pm
content: Quote from: nctnico on October 13, 2022, 05:51:21 pmsnort, yeah i forgot that i used simulator before hand. but simulator cant replicate real life, and not every part available in simulator. but thats off topic. btw i usually go perfboard when i want more permanent (working) circuit that i dont bother send to pcb house to make, for one off self hobby use. if we want argue most reliable circuit, real pcb is the way, but then its off topic again.cheers

author: noisyee
author_rank: Contributor
timestamp: October 14, 2022, 01:26:29 am
content: When I was in school, I used that kind of PCB SMD to DIP adapters a lot. They worked fine, OK, in most situations.In other situations, like Op amps with more than tens of MHz GBW, or modern high-speed digital devices, they cause more problems than convenient.Many technics were developed to solve that problems, like soldering a solid copper plate under that adapter, flying decoupling capacitors over the chip and so onChip sockets would perform even worse in those situations, and they are expensive too.Now I'm almost done with that adapters since PCB manufacturing is so much cheaper and faster than the old days. As for simple prototype verification, you can buy or design some specialized circuit model boards, like the Arduino and the TI DIYAMP-EVM. Breadboarding with them are much better than with a universal SMD to DIP adapter.https://www.ti.com/tool/DIYAMP-EVMAnd of course you can make some home-made PCB, the only problem is they requiring some chemicals or CNC machines.

author: artag
author_rank: Super Contributor
timestamp: October 14, 2022, 02:36:26 am
content: Quote from: noisyee on October 14, 2022, 01:26:29 amI still use proto boards for making things at home on minimal budget and low complexity, but everywhere I've worked, the practise has been to go straight to pcb.

author: noisyee
author_rank: Contributor
timestamp: October 14, 2022, 10:03:04 am
content: Quote from: artag on October 14, 2022, 02:36:26 amIt's harder to find a proto boards at my working place than find an empty PCB which suite the prototype circuits.But at home for simple circuits, anything easy to get are welcome.

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 14, 2022, 10:27:40 am
content: Quote from: noisyee on October 14, 2022, 01:26:29 amsome high speed IC/opamp require specialized EVM in close accordance to datasheet recommendation. i'm sure nctnico already aware of this when making his differential amplifier. even with real pcb made by cheap junk, the IC can oscillate, we need high speed design black belt to do it properly and compensate with cheap junk materials, with breakout or bread board they will simply go heywire to the last piece of your hair. and need more time than debugging real circuit to fondle simulator to get real life effect.