Electromagnetic Devices
Electromagnetic devices work based on the relationship between electrical current and a magnetic field. They are used to control valves, cooling and heating systems, relays, and electric motors. More ...
Direct Current
The nucleus of an atom is relatively heavy, so electricity primarily involves the flow of electrons. The nucleus of an atom generally doesn't move much. More ...
RMS Used in AC Circuit Analysis
Because the value of an AC signal is continuously varying, it would be difficult to use formulas such as ohms law. In the specific case of a sine wave, the Root Mean Square (RMS) of the wave is used instead. More ...
Alternating Current
With DC (Direct Current), electric current flows in only one direction. With AC (Alternating Current), current direction reverses periodically. More ...
Inductors in Series and Parallel
Inductances in series add like resistances in series. The total value is the sum of the individual values. Inductances in parallel values add up like the values of resistors in parallel. The reciprocal of total inductance is the sum of reciprocals of all the individual inductances. More ...
Superposition Theorem
The resistive networks that satisfy Ohm's law allow a number of simplifying approaches to be taken in their analysis. Circuit analysis by superposition replaces all voltage sources but one with short circuits, then using the summation rules of series-parallel combinations of resistors determine the voltage across and current in each branch due to the remaining voltage source, and then repeating this process for all voltage sources and superposing the results. More ...
Inductors in DC Circuits
When voltage first applied current through an inductive circuit is low because a magnetic field starts building in the coil, and this magnetic field creates a back electromotive force (EMF) that oppose the current in the inductor. More ...
Zener Diode
A zener diode is similar to a standard diode allowing current flow in the forward direction except the semiconductor is more heavily doped and this allows it to operate in the reverse-bias break down mode. More ...
Light Emitting Diode (LED)
An LED is a diode that converts electrical current directly into light and therefore it is more efficient than other sources of light which convert some energy into heat. When electrons recombine with holes in the depletion region they release energy in the form of light photons. More ...
Integrated Circuit Manufacturing Packaging
Before ICs can be put to their intended use they must be packaged. The package is responsible for interconnecting, powering, cooling, and protecting the IC. More ...
RC Filters
An RC filter can accept input sinewave signals and block certain bands of frquencies, thus allowing to pass only desired frquencies. This section describes passive RC filters. A passive RC filter uses only resistors and capacitors. More ...
Modern Semiconductor Manufacturing
The modern semiconductor manufacturing process sequence is the most sophisticated and unforgiving volume production technology that has ever been practiced successfully. It consists of a complex series of hundreds of unit process steps that must be performed very nearly flawlessly. More ...
How to Calculate Impedance
Impedance is one of the most difficult things the electronics technician student needs to calculate. To calculate impedance, you must know the value of all resistors and the impedance of all inductors and capacitors in the circuit. Then you can calculate impedance using a simple mathematical formula. More ...
How to Read a Capacitor's Values
Due to the limited space available for printing, physically small capacitors are especially difficult to read. Therefore capacitors use a wide variety of codes to describe their characteristics. More ...
