Politics/shame/advantages/dis... of carrier/carrier module PCBs for prototyping

[paulca]

So, you can buy bare bones breakouts of already functioning circuits.  You can breadboard them, but what about when you mount a bunch of these to a PCB?

I'm just tempted because the amount of effort to layout a working, correct MCU minimal circuit and source the components when you can just buy a 15x60mm board for < £5!

Obviously space I can see being an issue.  Sometimes said modules get in the way or do stuff you wouldn't want.  I don't see the point for simple circuits, but why can't I just....

#include "stm32f411.h"

and use the whole black pill?  The USB port even works!

I imaging that space = cost in PCB manufacture but with everything SMD there is plenty of space under the module and .. on the dark side.

[pcprogrammer]

That is how I do most of my projects. Buy modules and wire them together on a proto board. Not a bread board like you know with the holes and the spring contacts, because these can be troublesome, but the ones where you solder things together.

Only when done developing and there is a need for a proper pcb I will draw one up and order it.

My next project is to replace the transmitter and receiver of an old FischerTechnik 27MHz remote control set with STM32 MCU, NRF transceiver and motor driver modules. Have all the modules lying around so no high prices due to the shortages

[james_s]

If it's a one-off hobby project just wire the modules together, nothing wrong with that. If you're building a whole bunch of them then making a proper PCB is more sensible.

[paulca]

Its the middle ground.  For a "should survive a month or two" I'd happily DuPont lead modules together.

and yes... if I thought I had something good or "final" I could drop it all back to custom SMD.

It's .. is it worth dropping an BlackPill into a printed PCB versus the layout, sourcing, BOM purchase and soldering all the components for an STM32 circuit... for each and every prototype?

Edit, if I'm honest my STM32F411CE layout doesn't really use much less space!  I'm not soldering those 0203 100nF caps by hand or by air.  If I breath funny they'll be on the floor.

[thm_w]

Yes after a while I realized this is a better option for the projects I do.
You save time soldering, and you can just remove and reuse the mcu module if there is a layout error that requires a new design.

Of course a small compact product, it wont work. But anything where space and height is not too critical, its good.
If anything, it might reduce board size a bit because now you have two stacks of PCBs, and you can put parts under the module.

[paulca]

Quick and dirty.  Just as I like em.

[SiliconWizard]

If it's a one-off hobby project just wire the modules together, nothing wrong with that. If you're building a whole bunch of them then making a proper PCB is more sensible.

Yep. Given the cost of PCBs these days (and how fast you can get them), it makes sense rather than hand-wire everything, and it's tidier.

But for any product, that doesn't make sense.