Current and voltage are probably the most important electrical properties in any electrical circuit. They are the cornerstones of every other parameter and the first properties you look at when designing a circuit.
As you can imagine, for dynamic circuits, it is quite important to know the voltage and current at certain points in order to control the device operation or trigger certain action as well as calculate the heat dissipation.
Like voltage, current can a constant value (DC current) or a varying waveform oscillating at a certain frequency (AC current).
To measure current there are two popular ways of doing it: by measuring voltage drop on a resistor or by sensing a magnetic field in a conductor.
In this article, we will focus on how to sense a magnetic field in a conductor with the idea of measuring AC current using a tiny, cheap circuit.(more…)