Lithium Ion Battery Chemistry
Lithium-ion (Li-ion) batteries are one of the most common portable power sources used today. Impurities in the materials used to construct a lithium battery can cause it to overheat. More ...
Batteries
Early in the history of electrical science, laboratory physicists found that when metals came into contact with certain chemical solutions, voltages appeared between the pieces of metal. These were the first electrochemical cells. 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 ...
Circuit Analysis with Thevenin's theorem
Thevenins theorem states that Any linear electronic network containing only voltage sources, current sources and resistances can be replaced by an equivalent combination of a voltage source in a series connection with a resistance. More ...
Magnetism
Electric currents and magnetic fields are closely related. Whenever an electric current flows a magnetic field accompanies the current. When a wire is coiled up, the resulting magnetic flux becomes more concentrated. More ...
Electrical Charge
The forces between electrically charged particles are used in technologies such as printers, pollution filters, and spray guns used for painting cars and trucks. Static electricity is the study of phenomena that involve an imbalance of electrical charge. Although creating this imbalance typically requires moving charge around, once the imbalance is created, it often remains static for a long time. More ...
Conductors and Insulators
Materials can be classified depending on whether they allow charge to move. If charge can easily move through a material, these materials are called conductors. If charge cannot move through a material, then this material is called an insulator. More ...
Integrated Circuit Manufacturing Deposition
Many different types of thin films are used to manufacture integrated circuits, including thermal oxides, dielectric layers, epitaxial layers, polycrystalline silicon, and metal films. This article addresses two techniques for depositing such films. More ...
Planar Integrated Circuit Fabrication
The key unit process steps in IC fabrication, include oxidation, photolithography, etching, ion implantation, and metallization. Here, we describe the oxidation steps. 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 ...
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 ...
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 ...
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 CMOS Technology
The MOSFET (metal-oxide-semiconductor field-effect transistor) is the dominant device used in modern integrated circuits because it can be scaled to smaller dimensions than other types of devices. More ...

