electronic components

An electronic component is a basic electronic element usually packaged in a discrete form with two or more connecting leads or metallic pads. Components are intended to be connected together, usually by soldering to a printed circuit board, to create an electronic circuit with a particular function (for example an amplifier, radio receiver, or oscillator). Components may be packaged singly (resistor, capacitor, transistor, diode etc.) or in more or less complex groups as integrated circuits (operational amplifier, resistor array, logic gate etc.)
[edit] Components
Very often electronic components are mechanically stabilized, improved in insulation properties and protected from environmental influence by being enclosed in synthetic resin
Components may be passive or active:
Passive components are those that do not have gain or directionality. [1] In network analysis they are called electrical elements.
Active components are those that have gain or directionality, in contrast to passive components, which have neither. They include semiconductor devices and vacuum tubes (valves).
[edit] Terminals and connectors
Devices to make electrical connection
Terminal
Connector
Socket
Screw terminal, Terminal Blocks
Header
Closed
[edit] Cords
Cables with connectors or terminals at their ends
Power cord
Patch cord
Test lead
[edit] Switches
Components that may be made to either conduct (closed) or not (open)
Switch - manually operated switch
Keypad - small array of pushbutton switches
Relay - Electrically operated switch. This is a mechanical component, unlike the Solid State Relay
Reed switch - Magnetically activated switch
Thermostat - Thermally activated switch
Circuit Breaker - Over-current activated switch
Limit switch - Mechanically activated switch
Mercury switch
Centrifugal switch
[edit] Resistors
Components used to resist current.
See the Transducer section below for resistors used to sense environmental conditions (Thermistor, Photo resistor, RTD...)
See the Protection section below for resistors used for current or voltage limiting (MOV, Inrush Limiters...)
Resistor - fixed value
Resistor network - array of resistors in one package
Trimmer - Small variable resistor
Potentiometer, Rheostat - variable resistor
Heater - heating element
Resistance wire - wire of high-resistance material, similar to heating element
Thermistor - temperature-varied resistor
Varistor - voltage-varied resistor
[edit] Protection devices
Passive components that protect circuits from excessive currents or voltages
While these components technically belong to the Wire, Resistor and Vacuum classes, they are grouped here based on their use.
Active components that perform a protection function are in the Semiconductor class, below.
Fuse - Over-current protection, one time use
Resettable fuse (PolySwitch, self-resetting fuse)- Over-current protection, resettable
Metal Oxide Varistor, Surge Absorber (MOV) - Over-voltage protection. These are passive components, unlike the TVS
Inrush current limiter - protection against initial Inrush current
Gas Discharge Tube - protection against high voltage surges
Circuit Breaker - Over-current activated switch
Spark gap - two electrodes with a gap in between to create arcing
Filament lamp
GFCI or RCD
[edit] Capacitors
Components that store electrical charge in an electrical field. Capacitors are used for filtration in the electronic circuits. Capacitors in general pass changing (e.g. AC) and block unchanging (e.g. DC) voltage levels.
Capacitor - fixed capacitance
Capacitor network (array)
Variable capacitor - change the capacitance
Varicap diode - variable capacitor come diode
[edit] Magnetic (inductive) devices
Electrical components that use magnetism
Inductor, coil, choke
Variable inductor
Saturable Inductor
Transformer
Magnetic amplifier (toroid)
Ferrite impedances, beads
Motor / Generator
Solenoid
Speaker / Microphone
[edit] Networks
Components that use more than one type of passive component
RC network - forms an RC circuit, used in Snubbers
LC Network - forms an LC circuit, used in tuneable transformers and RFI filters
[edit] Piezoelectric devices, crystals, resonators
Passive components that use piezoelectric effect
Components that use the effect to generate or filter high frequencies
Crystal - Is a ceramic crystal used to generate precise frequencies (See the Modules class below for complete oscillators)
Ceramic resonator - Is a ceramic crystal used to generate semi-precise frequencies
Ceramic filter - Is a ceramic crystal used to filter a band of frequencies such as in radio receivers
Surface Acoustic Wave (SAW) filters
Components that use the effect as mechanical Transducers.
Ultrasonic motor - Electric motor that uses the piezoelectric effect
For piezo buzzers and microphones, see the Transducer class below
[edit] Power sources
Sources of electrical power
Battery - acid- or alkali-based power supply
Fuel cell - an electrochemical generator
Power supply - usually a mains hook-up
Photo voltaic device - generates electricity from light
Thermo electric generator - generates electricity from temperature gradients
Electrical generator - an electromechanical power source
[edit] Transducers, sensors, detectors
Transducers generate physical effects when driven by an electrical signal, or vice-versa.
Sensors (detectors) are transducers that react to environmental conditions by changing their electrical properties or generating an electrical signal.
The Transducers listed here are single electronic components (as opposed to complete assemblies), and are passive (see Semiconductors and Tubes for active ones). Only the most common ones are listed here.
Audio (see also Piezoelectric devices)
Loudspeaker - Magnetic or piezoelectric device to generate full audio
Buzzer - Magnetic or piezoelectric sounder to generate tones
Position, motion
Linear variable differential transformer (LVDT) - Magnetic - detects linear position
Rotary encoder, Shaft Encoder - Optical, magnetic, resistive or switches - detects absolute or relative angle or rotational speed
Inclinometer - Capacitive - detects angle with respect to gravity
Motion sensor, Vibration sensor
Flow meter - detects flow in liquid or gas
Force, torque
Strain gauge - Piezoelectric or resistive - detects squeezing, stretching, twisting
Accelerometer - Piezoelectric - detects acceleration, gravity
Thermal
Thermocouple, thermopile - Wires that generate a voltage proportional to delta temperature
Thermistor - Resistor whose resistance changes with temperature, up PTC or down NTC
Resistance Temperature Detector (RTD) - Wire whose resistance changes with temperature
Bolometer
Thermal cutoff - Switch that is opened or closed when a set temperature is exceeded
Magnetic field (see also Hall Effect in semiconductors)
Magnetometer, Gauss meter
Humidity
Hygrometer
Electromagnetic, light
Photo resistor - Light dependent resistor (LDR)
[edit] Solid State components, Semiconductors
Electronic control components with no moving parts. Active components
[edit] Diodes
A device which conducts electricity in only one direction.
Standard Diode, Rectifier, Bridge Rectifier
Schottky Diode, Hot Carrier Diode - super fast diode with low forward voltage drop
Zener Diode - lets electricity flow "backwards" if it is suitably high in voltage
Transient Voltage Suppression Diode (TVS), Unipolar or Bipolar - used to block high-voltage spikes
Varactor, Tuning diode, Varicap, Variable Capacitance Diode - A diode come capacitor
Light Emitting Diode (LED) - A diode which gives out light
LASER Diode - A laser LED
Photodiode - Only passes power when in light
Solar Cell, photovoltaic cell, PV array or panel
Avalanche Photodiode
Diode for Alternating Current (DIAC, Trigger Diode, SIDAC)
Current source Diode
Peltier cooler
[edit] Transistors
Bipolar transistors
Bipolar Junction Transistor (BJT, "transistor") - NPN or PNP
Photo transistor
Darlington transistor - NPN or PNP
Photo Darlington
Sziklai pair (Compound transistor, complementary Darlington)
Field effect transistor (FET)
Junction Field Effect Transistor (JFET) - N-CHANNEL or P-CHANNEL
Metal Oxide Semiconductor FET (MOSFET) - N-CHANNEL or P-CHANNEL
MEtal Semiconductor FET (MESFET)
High Electron Mobility Transistor (HEMT)
Thyristors
UniJunction Transistor (UJT)
Programmable UniJunction Transistor (PUT)
Silicon Controlled Rectifier (SCR)
Static Induction Transistor/Thyristor (SIT, SITh)
TRIode for Alternating Current (TRIAC)
Composite transistors
Insulated Gate Bipolar Transistor (IGBT)--

are those in which current or voltage may vary continuously with time to correspond to the information being represented. Analog circuitry Analog circuitry is constructed from two fundamental building blocks: series and parallel circuits. In a series circuit, the same current passes through a series of components. A string of Christmas lights is a good example of a series circuit: if one goes out, they all do. In a parallel circuit, all the components are connected to the same voltage, and the current divides between the various components according to their resistance.

A simple schematic showing wires, a resistor, and a battery.
The basic components of analog circuits are wires, resistors, capacitors, inductors, diodes, and transistors. (Recently, memristors have been added to the list of available components.) Analog circuits are very commonly represented in schematic diagrams, in which wires are shown as lines, and each component has a unique symbol. Analog circuit analysis employs Kirchhoff's laws: all the currents at a node (a place where wires meet) must add to 0, and the voltage around a closed loop of wires is 0. Wires are usually treated as ideal zero-voltage interconnections; any resistance or reactance is captured by explicitly adding a parasitic element, such as a discrete resistor or inductor. Active components such as transistors are often treated as controlled current or voltage sources: for example, a field-effect transistor can be modeled as a current source from the source to the drain, with the current controlled by the gate-source voltage.
When the circuit size is comparable to a wavelength of the relevant signal frequency, a more sophisticated approach must be used. Wires are treated as transmission lines, with (hopefully) constant characteristic impedance, and the impedances at the start and end determine transmitted and reflected waves on the line. Such considerations typically become important for circuit boards at frequencies above a GHz; integrated circuits are smaller and can be treated as lumped elements for frequencies less than 10 GHz or so.
An alternative model is to take independent power sources and induction as basic electronic units; this allows modeling frequency dependent negative resistors, gyrators, negative impedance converters, and dependent sources as secondary electronic components.
[edit] Digital circuits