It all started when I noticed that this product has it:
It had three capacitors to perform some power filtering.
When I asked why, I was told that since this sensor is powered by a 5-12V wide voltage supply, they parallel several small capacitors between VCC and GND for power filtering.
So… questions:
What is power filtering exactly?
Why is it needed with wider voltage ranges?
How do the capacitors in parallel “filter” things?
(MOST IMPORTANT) Is there a way to simulate circuits online, and go as far as (a) Providing unfiltered “messy” voltage (b) "See the provided voltage in real time (c) Apply the small capacitors (d) See in real time how the voltage is filtered?
(5) (EVEN MORE IMPORTANT) What textbook would you recommend me to study to actually get electronics? Is there something with a very practical stint? I have my multimeter, I can get components, I (sort of) can solder, I have my breadboard... I would love to actually see what I study. And when it's impossible/unrealistic to build something, I want to be able to simulate it fully with some software.
The real world is messy. A 5V supply is really 4.5 to 5.5V and in addition there is high frequency "noise" from interference from other supplies. Perhaps voltage spikes from the power line (mains) etc. Power filtering reduces this noise (but not the 4.5 to 5.5).
Note: I know the sensor has a wide range of voltage it will work at. The 5V above is just to show that the 5V is NOT 5.0000 Volts.
Power filtering is similar to an automotive shock absorber, it slows down any changes with a goal of slowing them down to the point they never make it to the circuit.
Its needed at all voltages. The likely reason for the multiple is they have to deal with a higher voltage than 5V. So they cost more in larger sized. So 3 smaller caps will do the same as one larger more expensive cap.
Caps in parallel add. So two 1µF capacitors in parallel act like one 2 µF cap.
Unlikely. THe input noise is not defined anywhere to my knowledge. Yes there are military, automotive, and likely other specifications but they are of little use to the hobbyist.
Sorry I can't help you here. I learned "by fire" before the internet. You need some kind of a primer.
I'm not familiar with how the current spice type programs deal with noise. I know spikes can be simulated. I suggest you see what they can do as even if you cannot fully simulate the noise and perturbations on the power line you will be able get a sense of how different filters can reduce noise.
Perhaps the nspice category.
Multiple caps in paralel are often apllied because they 'react' faster than one single larger cap.
In laptops they have 20 or more equal caps in paralel to filter GHz noise.
Capacitors have what’s called ESR, equivalent series resistance.
We want this resistance small in our power circuits.
When resistors are placed in parallel, the result is a lower overall resistance.
4 parallel capacitors each with 4 ohms of ESR, gives an overall resistance of 1 ohm.
In addition to that capacitors have inductance, which means that above a certain frequency they stop behaving as capacitors and become inductors, making them useless as capacitors above that frequency. Electrolytic capacitors are typically constructed of rolled up layers of foil and insulation, rolled up means more inductance. Ceramic capacitors have layers of flat plates, which means much less inductance. Mixing the 2 types extends the frequency range at which they are effective.
As for learning electronics I find that understanding Ohms law, Kirchhoff's circuit laws and basic physics, particularly conservation of energy, goes a long way to understanding any circuit. A quick glance at a lot of circuits designed by people with no understanding of these laws reveals a circuit that cannot possibly work because the circuit doesn't respect basic laws. If you don't know them look them up and learn them, then ask yourself how they apply to any circuit you see here and elsewhere.
