How do basic analog components like diodes and capacitors work?

Hint: Think of the basic building blocks of analog circuits.

An introduction to diodes can be found here: Hardware FYI-What are Diodes and their applications?

Regarding capacitors, let’s start with a high-level definition:

Capacitors both store and release energy. Capacitors store the potential energy in the electric field, whereas batteries accumulate the energy in the form of chemical energy, which is later changed to electric energy. Capacitors come with features such as easy charging/discharging capabilities.

In consumer-electronic applications, they’re mainly used for two critical functions:

  1. Filtering (combined with inductors and resistors to form 1st/2nd order filters - i.e. filtering out noise/specific frequencies)
  2. Stabilizing power rails

If you were to take an electric skateboard for example, there’s a wide range of components that run on different power rails (5V, 12V, 24V, etc.).

Voltage sources sag when you draw current from them. Motor brushes (and lots of other components) produce horrendous voltage spikes that you want to filter out of your digital circuitry. The capacitor acts as a very close source of power. You pull your high speed power from the capacitor and the power source slowly charges the capacitor.

When done properly, everything works to spec. When making a commercial product and done improperly you get a product that has very odd bugs, normally tied to high load as the voltage really sags(sags= goes below what it needs to be).

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