Bipolar Transistors
Transistors are semiconductor devices used to amplify or switch electronic signals. Transistors are one of the basic building blocks of modern electronics. There are basically two types of transistors, Bipolar Junction Transistors (BJT) and Field Effect Transistors (FET). 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 ...
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 ...
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 ...
Electrical Transformers
A transformer is an electrical device that uses the principle of magnetic induction to step voltage up or step down. Inversely it increases or decreases the current available at the different voltages. More ...
Inductors in Series and Parallel
With inductors connected in series, the total inductance is the sum of the inductances of the individual inductors With inductors in parallel, the reciprocal of the equivalent inductance is the sum of the reciprocals of the inductors connected in parallel. More ...
Use a Resistor to Measure Inductance
Inductance is usually measured by using an LCM multimeter. It can also be mesured using a resistor. With the resistor method, you adjust the frequency of a sine wave until the AC voltage accross the resistor and inductor are equal. Then using a formula to calculate the inductance. More ...
Integrated Circuit Fabrication Masks
A mask in IC Fabrication is a master template for an IC design. A light-sensitive material, is applied on the wafer. The mask as well as a wafer are inserted in a lithography scanner. 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 ...
Transformers
Transformers work according to the principle of electromagnetic induction. If the first coil carries sine-wave ac of a certain frequency, then the induced current will be sine-wave ac of the same frequency in the second coil. 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 ...
Integrated Circuit Photoresist Process
The semiconductor photolithography process involves coating the substrate with A light-sensitive chemical layer called photoresist. Light is projected through a mask onto the substrate causings photoresists to react chemically. More ...
Inductor Mutual Inductance and Coefficient of Coupling
Mutual Inductance the property of a coil in which it opposes the change of current in another coil. The coefficient of coupling between two coils is the fraction of magnetic flux produced by the current in one coil that links with the other coil. More ...
