Inductive Reactance
The opposition that the coil offers to ac is called inductive reactance. Like resistance, reactance is measured in ohms. Unlike resistance, reactance changes with frequency. And in an Inductor, the Voltage leads the Current by 90 degrees. 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 ...
What Is an Electronic Circuit?
Circuits provide a path for current to flow. To be a circuit, this path must start and end at the same point. In other words, a circuit must form a loop. 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 ...
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 ...
Junction Field Effect Transistor (JFET)
A Junction Field Effect Transistor (JFET) consists of a channel and a pn junction. The gate controls the conductance of the channel. A JFET is a voltage controlled device, therefore no current flows into the gate. 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 ...
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 ...
Electric Fields and Static Electricity
Static electricity is a phenomenon caused by a buildup of unbalanced electric charge that is not moving. We are all familiar with the static electric charge caused by dragging our feet across a carpet and then the sudden static discharge caused by grabbing a door knob. 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 ...
Common Emitter Configuration Transistor Biasing
To design a common emitter amplifier circuit, use a voltage divider with resistors selected to set the base voltage at the center of the transistor's linear region. Then, through a DC blocking capacitor, apply a waveform to the transistor's base. More ...
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 ...
Triac
You can of a triac as two back-to-back SCRs with the cathode of one SCR connected to the anode of the other. The gates are connected together. Because we have a two SCRs configuration you can control the switching of both half cycles. More ...
Alternating Current
With DC (Direct Current), electric current flows in only one direction. With AC (Alternating Current), current direction reverses periodically. More ...
