Silicon Controlled Rectifier (SCR)
A Silicon Controlled Rectifier (SCR) is a 4-layer diode that is controlled by a gate signal. It ca be turned on by a pulse on the gate. 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 ...
Magnetism
Magnetism is the force exerted by magnets when they attract metals or attract and repel each other. 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 ...
Semiconductor Manufacturing Process Sequence
Semiconductor manufacturing consists of a series of sequential process steps in which layers of materials are deposited on substrates, doped with impurities, and patterned using photolithography to produce ICs. More ...
EMI, RFI, EMC, EMS, What's the Difference?
EMI, RFI, EMC, and EMS all refer to different aspects of radio frequency interference which may cause elecronic devices to malfunction. Correcting these problems can be an art and a science. More ...
Introduction to Integrated Circuit Manufacturing
An integrated circuit is an ensemble of active (e.g., transistors) and passive devices (e.g., resistors, capacitors, and inductors) formed on and within a single-crystal semiconductor substrate and interconnected by a metallization pattern. More ...
Magnetism Permeability and Retentivity
Permeability is a property of a material that describes the ease with which magnetic flux is established in the material. Retentivity is a materials ability to retain a certain amount of residual magnetism after the magnetizing force is removed. 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 ...
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 ...
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 ...
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 ...
Transforming Sources for Circuit Analysis
Kirchhoff's laws and Ohm's laws can get pretty laborious when you're analyzing complex circuits. Through a transformation technique, you modify a complex circuit so that in the transformed circuit, the devices are all connected in series or in parallel. After the transformation, you no longer need to systematically apply Kirchhoff's laws. More ...
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 ...

