Basic Electronics



 

Basic Electronics

Inductors:

Inductors store magnetic energy (magnetic field of a coil). The voltage across an inductor is proportional to the rate of change of the current through the inductor.

Schematic symbol(s)

Inductance is the proportionality between the voltage across an inductor and the rate of change of the current through it.

The unit of inductance is the   henry.

     (A henry is a volt-second per ampere.)

Practical information: 

Inductance: Typical inductance values are measured in henries (H), millihenries (mH = 10⁻³ H) and microhenries (μH = 10⁻⁶ H).

Series resistance: The ideal inductor has zero resistance, however real inductors are made from many turns of wire. The resistance of the wire is often significant and can be included in the circuit model as a resistor in series with the inductor.

Core materials: The  inductance of a coil can be greatly increased by placing a magnetic material inside the coil. The type of magnetic material inside the coil determines the detailed electrical characteristics of the inductor, such as eddy current losses and high frequency performance. In this class we will not be concerned with these details. It is however necessary to understand that these details are responsible for the wide variety of types of inductors.

Inductors in parallel: 

The equivalent inductance of inductors in parallel is the reciprocal of the sum of the reciprocals of the inductances of all of the parallel inductors.

Inductors in parallel: 

Inductors in series:  The equivalent inductance of inductors in series is the sum of the inductances of all of the inductors.

Inductors in series:  

 

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