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 ...
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 ...
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 ...
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 ...
How to Read a Capacitor's Values
Due to the limited space available for printing, physically small capacitors are especially difficult to read. Therefore capacitors use a wide variety of codes to describe their characteristics. More ...
Electronics Lab
Even though an electronic circuit may appear to work on paper, and maybe even in a circuit simulator, it's always important to test it in the real world. Prototype circuits can be built using a solderless breadboard. More ...
Lead-Acid Battery Chemistry
As a lead-acid battery is repeatedly recharged, sulfation will build-up on the plates and the battery will begin to loose its capacity to restore to a full charge and eventually must be replaced. 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 ...
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 ...
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 ...
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 ...
Alternating Current
With DC (Direct Current), electric current flows in only one direction. With AC (Alternating Current), current direction reverses periodically. 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 ...
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 ...
