Circuit, PCB analysis tools

zapta

@joergs5 said in Circuit, PCB analysis tools:

I tried LTSpice, but I did not like the handling very much

This guy has a few episodes demonstrating MicroCap. Apparently it's also free now after the developer retired.

https://www.youtube.com/watch?v=bjn-252Oo7A

If you look for a user friendly program, you may want to try this https://www.circuitlab.com/

JoergS5

@zapta thanks for the youtube link, the gallery of voltmeters signals some electronic experience

Thanks for the CircuitLab hint, but I don't like online tools much*), I'll stick at Micro-Cap and for PCB design KiCad seems to be interesting also.

*) IP is not the reason, the reason is they want my private data sooner or later.

BTW thanks for your stepper motor analyzer, this inspired me to develop similar Duet extensions!

zapta

I started this morning to learn microcap, following the user manual. So far it looks very thorough and reasonable UI.

rjenkinsgb

@joergs5 said in Circuit, PCB analysis tools:

and for PCB design KiCad seems to be interesting

For PCB design, I'd highly recommend EasyEDA, it is an exceptionally good, free, PCB program (having used quite a few different and often ludicrously expensive ones over some decades).

PCR

@rjenkinsgb yep. Or kicad 6.0

zapta

@rjenkinsgb, coincidently I started using EasyEDA yesterday after looking at it a few times over the years, and it improved greatly and has a more modern and intuitive UI than Kicad.

The OP seems to prefer local apps over web apps so may not be a good fit. Also, I am not sure how does it compare with Kicad for more complex projects, but it definitely a good choice for smaller projects and the integration with JLCPCB part library and footprints is great.

This is my first project, a work in progress. Most of the work is in aligning all the parts and EasyEDA makes it easier.

JoergS5

@zapta said in Circuit, PCB analysis tools:

The OP seems to prefer local apps over web apps so may not be a good fit.

this is only my personal taste, please everyone may go ahead talking about every software. Because this thread is meant to be a general discussion for all users, it may be interesting for others to use online tools, also. (And there are very good online tools like GeoGebra without registering, I use some of them).

I have the same problem with Micro-Cap, because it's not open source, I cannot modify it. But being so powerful, I'll proceed with it, looking at KiCad at the same time.

zapta

@joergs5, it seems that EasyESA also support simulation with an easy to use GUI which is very nice https://www.youtube.com/watch?v=5eoOV1IxkIU

@PCR, I see that Kicad 6 is out. Originally it was supposed to be released May 2021. I was waiting for it. Will see how difficult the transition is.

BTW, all of Duet's board are designed with Kicad.

rjenkinsgb

@zapta said in Circuit, PCB analysis tools:

The OP seems to prefer local apps over web apps

There is a fully downloadable version of EasyEDA - I don't like using anything web-based for files I want to control!

It can also import kicad files; I've used it to view Duet board files.

I'm criticizing kicad in any sense, just being sure there are no misunderstandings re. easyeda.

JoergS5

I have a different question about which reflow oven to use, maybe someone can help me.

I am thinking about buying a T-962A reflow oven and then modifying it (better temperature control, better heating). Is this a good idea or are there better options? I plan to develop small PCBs for interfaces, maybe 100x200 mm maximal, but two sides.

JoergS5

@rjenkinsgb EasyEDA is a nice program. I appreciate that there are a lot of circuits of other users where I can learn from them. Micro-Cap and KiCad have their uses also.

zapta

@joergs5 said in Circuit, PCB analysis tools:

T-962A reflow oven

I used a similar over in the past, with stencils, paste, and manual vacuums component picker but gave it away. It was too much of a hassle for my use cases.

Now I just solder the parts using tweezers and a fine solder iron, and with the Chinese stereo microscope I have, I can get down to 0402 components and 0.5mm pitch ICs.

Another option I am using now is JLCPCB SMD service which is reasonably priced so I try to include as many components that are available at JLCPCB and then solder the rest by hand.

I used to have a fancy Metcal soldering system but gave it away and now using this cheapo chineese that give me about the same results. They are so cheap that I have a few of them, each each a different tip and temperature setting. https://www.aliexpress.com/item/4000129151281.html

For manual soldering, I recommend getting good flux paste such as AmTech (spelling?) and a cheap optical stereo microscope, you don't need high magnification, ~x5 works well for PCB worked. I am using this one https://www.amazon.com/gp/product/B00A15N1ZA there are many models, including ones with long boom base. The light ring is important.

YMMV.

rjenkinsgb

@joergs5 said in Circuit, PCB analysis tools:

I am thinking about buying a T-962A reflow oven

We use normal (good) temperature controlled irons for general work, and I have a cheap ebay hot air tool that works fine for surface mount ICs, when needed.

If you want complete boards, use JLCPCB - it's cheaper to have them also supply the parts and assemble the PCBs, than to buy the separate components!

dc42

@JoergS5 I use a domestic electric hotplate for reflow soldering small prototype boards. No need for a reflow oven unless you are going into production.

JoergS5

Thank you all for your feedback, so a reflow oven would be exaggerated. I'll look into your proposals.

JoergS5

@dc42 said in Circuit, PCB analysis tools:

domestic electric hotplate for reflow soldering

that's intersting, maybe I can solder with this my solar modules (I bought raw cells) with tab wire as well. I can buy a cheap one for 260 °C. Is this sufficient, or do I need one with variable temperature, there is one for 50 to 350 °C.

The cheap one is https://www.amazon.co.uk/POHOVE-Heating-Soldering-Heating-Soldering-Laboratory/dp/B08XJGJN59 and the 50..350 is https://www.amazon.co.uk/Microcomputer-Electric-Heating-Preheating-Soldering/dp/B07WJ4THGP

zapta

@joergs5 , you may want to look also for hot plates that are intended for PCB reflow. There are many on Aliexpress and amazon and typically they come with good temperature display and control.

E.g.

https://www.aliexpress.com/item/1005002103189787.html

Make sure to pick a hot plate that gets hot enough to reflow the solder you use. Some plates are used for 'preheating' which requires lower temperatures, below solder melting point.

https://www.youtube.com/watch?v=bz6OONg5hmg

You may want to look also on youtube for PCB paste/stencil techniques.

JoergS5

@zapta thanks a lot for your hints! I am used to look for videos first, but in this case I forgot to search for it.

There are big differences of prices...

I saw the video now, I am really surprised to learn something new, that avoiding temperature shock is an important reason.

zapta

@joergs5, when I was still using the reflow oven I looked for way to simplify the paste and part placement process. Some of my attempts included 3D printed parts like the ones below but eventually gave up on solder paste all together. YMMV

https://www.thingiverse.com/thing:1119914

https://www.thingiverse.com/thing:675336

https://www.thingiverse.com/thing:607270

https://www.thingiverse.com/thing:530949