> My question (hopefully not stupid, but possibly naive as I am just
> a physicist and not an EE) is this: can't the same thing be done
> with a series inductor? In that case, energy stored in the
> magnetic field of the inductor would be available to resist
> attempted changes in the voltage level. It seems to me that this
> should work to help clean up a +5V logic power rail, and I believe
> this is done with SMPSs. But as much as I see people talking
> about bypass capacitors, I don't recall much talk of "bypass
> inductors" (or whatever it would be called). Are there good reasons
> not to do this, maybe I^2R power dissipated in the inductor?

Michael,

I've seen a lot of inductors used for the purpose of "smoothing out" the
voltage in the 1960's era radios.  They are not used nowadays for several
reasons: capacitors are a lot cheaper, smaller, and lighter.

> If this is possible, what rules of thumb might apply to the
> values and types of inductors to be used?

It all depends on the frequency and current through the choke.  I.e., you
will need a large inductor in a circuit which consumes a lot of current and
where the current is changing slowly.  On the other hand, if you plan to use
it to choke out RF frequency in the AF cascade of a homemade radio, you will
only need a small inductor.

There are formulas that help you calculate the value of inductance, but I
usually trust my intuition for non-critical applications like rf mic's.  I
suppose most engineers are like that.   Otherwise, how would you explain the
number of 10K resistors in any given electronic circuit?  >;)

Sincerely,

Vitaliy

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