Re: what's the difference between passive and active compone
I would say that (surprisingly i am not sure, but that's a very good thing)
active devices are usually semiconductor devices that depend on (electron and holes) carriers for their operation, and hence require a source of energy(supply) that they can use to amplify signals (meaning generate their own power gain)
passive devices are just materials that can dissipate or store energy. They can very well be made out of semiconductor devices, but in reality we get a lot of parasitics when we do that.
The presence or absence of a source of energy determining the device operation would then be a fundamental difference.
Active devices have memory since they can be modeled as a combination of passive devices that can be used as memory(e.g capacitors) so this is not a difference.
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If you look at active device models (e.g. mosfet), you will always find a dependent current or voltage source, which implies a source of power and a biasing point required for the derivation of such a model, whereas if you make a very detailed model of a spiral inductor, you will get only resistors, capacitors, and inductors but no dep. sources. so this seems to be the difference
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