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 ...
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 ...
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 ...
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 ...
The Diode
A diode is a semiconductor component designed to allow current to pass in one direction. To form a diode, a P type semiconductor is joined with an N type of the same semiconductor element, forming a P-N junction. Diodes are used for turning AC to DC, isolating signals, and mixing signals. 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 ...
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 ...
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 ...
Integrated Circuit Manufacturing BiCMOS Technology
BiCMOS is a technology that combines both CMOS and bipolar device structures in a single IC. The reason to combine these two different technologies is to create an IC chip that has the advantages of both CMOS and bipolar devices. More ...
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 ...
Phase shift in AC Circuits
In an AC circuit with a capacitor or an inductor there is a phase shift between voltage and current. In this article you learn how to calculate the amount of that phase shift. More ...
Integrated Circuit Manufacturing Etching
photolithography is the process of transferring patterns to photoresist covering the surface of a semiconductor wafer. To produce circuit features, these resist patterns must be transferred into the underlying layers of the device. Pattern transfer is accomplished by an etching process that selectively removes unmasked portions of a layer. More ...
Operational Amplifier
An operational amplifier (op amp) is an amplifier circuit with a differential input, in other words it amplifies the voltage difference between its two inputs. The open-loop gain of an op amp is typically very large so normally, it's configured with negative feedback to reduce the gain. 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 ...
