Comment by btbuildem | Hacker News Reader

Comment by btbuildem | Hacker News Reader

> so I searched the web and found tinkercad.com has a circuit simulator where you can drag and drop all the components and see if and how it works. It worked for simple circuits, but for mine, the astable multivibrator, it didn’t for some reason. I tried falstad.com/circuit; the same thing happened. It also didn’t work. I searched the web for the reason, and I’ve noticed that sometimes these simulators don’t work well for complex circuits.

If anyone knows of a hobby-grade circuit design and simulation software (on macos! or online), I'd be so grateful to have it mentioned. I've tried kicad, diylc, fritzing, and a few other options, and nothing really "works". It's like the minds of people who created these are broken in a certain tragic way that just does not yield itself to making useable software.

The holy grail for me would be something that allows to design the electronic, then spatial aspects of circuits -- from testing the functionality, to making the board (and bonus points for stripboard support!)

The naive programmer in me wants to assume, "It can't possibly be that hard to simulate a circuit," and get to work on prototyping my own simulation engine but the fact that this apparently has not ben adequately solved yet gives me pause.

It depends on what level of detail you want the simulation to have. Boolean logic is easy. Analog circuits operating in certain (very limited) domains are straightforward. But - noting that what follows is well out of the realm of my experience - in other domains you have to account for things like RF characteristics and quantum effects in the semiconductors.

Imagine trying to simulate something that used water in tubes to implement logic, except it's analog logic and there's resonance and some of the joints start leaking when they exceed a certain pressure and etc.

SPICE (simulation program with integrated circuit emphasis) is open-source. As is ngspice, next generation SPICE.

LT-spice is just a graphical front end to make SPICE easier to use.

Yeah, analog is hard.

As a practicing EE and naive programmer, It is pretty hard to build a simulation engine for electronics and even harder to build a performant engine. SPICE does this with huge matrices of differential equations and math tricks.

Theres an interesting article by Mike Engelhardt (author of LTspice) which gives hints on the details of their implementation.

https://www.analog.com/media/en/technical-documentation/tech...

For hobby use I have found it best to do circuit design and simulation in different pieces of software. LTspice for simulation and KiCad or EasyEDA for PCB design.

Fully agree that your mind has to be a particular type of broken to click with all of these. I love LTspice for its simulation tools, for example the ability to vary a component value over time in a transient simulation, but it is a software that fights you at every turn when you try to learn it.

> astable multivibrator

come again?

Astable means that it keeping switching, like a clock signal, as opposed to a lightswitch which is bistable (will stay where it is in either position) https://en.wikipedia.org/wiki/Multivibrator

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