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Product range:

Terminals and connectors

Devices to make electrical connection
Connector Socket
Screw terminal, Terminal Blocks
Pin header

Cable assemblies

Cables with connectors or terminals at their ends
Power cord
Patch cord
Test lead


Components that can pass current (“closed”) or break the flow of current (“open”)
Switch – Manually operated switch. Electrical description: SPST, SPDT, DPST, DPDT, NPNT (general)
Technology: slide switches, toggle switches, rocker switches, rotary switches, pushbutton switches
Keypad – Array of pushbutton switches
DIP switch – Small array of switches for internal configuration settings
Footswitch – Foot-operated switch
Knife switch – Switch with unenclosed conductors
Micro switch – Mechanically activated switch with snap action
Limit switch – Mechanically activated switch to sense limit of motion
Mercury switch – Switch sensing tilt
Centrifugal switch – Switch sensing centrifugal force due to rate of rotation
Relay – Electrically operated switch (mechanical, also see Solid State Relay below)
Reed switch – Magnetically activated switch
Thermostat – Thermally activated switch Humidistat –
Humidity activated switch
Circuit Breaker – Switch opened in response to excessive current: a resettable fuse


Pass current in proportion to voltage (Ohm’s law).
Resistor – fixed value Power resistor – larger to safely dissipate heat generated
SIP or DIP resistor network – array of resistors in one package
Variable resistor
Rheostat – Two terminal variable resistor (often for high power)
Potentiometer – Three terminal variable resistor (variable voltage divider)
Trim pot – Small potentiometer, usually for internal adjustments
Heater – heating element
Resistance wire, Nichrome wire – wire of high-resistance material, often used as heating element
Thermistor – temperature-varied resistor
Humistor – humidity-varied resistor
Varistor, Voltage Dependent Resistor, MOV – Passes current when excessive voltage present

Protection devices

Passive components that protect circuits from excessive currents or voltages
Fuse – Over-current protection, one time use
Circuit Breaker – Resettable fuse in the form of a mechanical switch
PolySwitch or Resettable fuse – Circuit breaker action using solid state device
Ground-fault protection or Residual-current device – Circuit breaker sensitive to mains currents passing to ground
Metal Oxide Varistor, Surge Absorber (MOV), TVS – Over-voltage protection.
Inrush current limiter – Protection against initial Inrush current
Gas Discharge Tube – Protection against high voltage surges
Spark gap – Electrodes with a gap to arc over at a high voltage
Lightning arrester – Spark gap used to protect against lightning strikes


Components that store and release electrical charge. Used for filtering power supply lines, for tuning resonant circuits, and for blocking DC voltages while passing AC signals, among numerous other uses.
Capacitor – fixed capacitance Capacitor network (array)
Variable capacitor – Adjustable capacitance Tuning capacitor – Variable capacitor for tuning a radio, oscillator, or tuned circuit
Trimmer capacitor – Small variable capacitor usually for internal adjustments
Varicap diode – AC capacitance varies according to the DC voltage applied.

Magnetic (inductive) devices

Electrical components that use magnetism
Inductor, coil, choke
Variable inductor
Saturable Inductor
Magnetic amplifier (toroid)
Ferrite impedances, beads
Motor / Generator
Speaker / Microphone


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

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

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

Transducers, sensors, detectors

1.Transducers generate physical effects when driven by an electrical signal, or vice-versa.
2.Sensors (detectors) are transducers that react to environmental conditions by changing their electrical properties or generating an electrical signal.
3.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

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 – Device for measuring the power of incident electromagnetic radiation
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


Electromagnetic, light
Photo resistor – Light dependent resistor (LDR)



Conduct electricity easily in one direction, among more specific behaviors.
Standard Diode, Rectifier, Bridge Rectifier
Schottky Diode, Hot Carrier Diode – super fast diode with lower forward voltage drop
Zener Diode – Passes current in reverse direction to provide a constant voltage reference
Transient Voltage Suppression Diode (TVS), Unipolar or Bipolar – used to absorb high-voltage spikes
Varactor, Tuning diode, Varicap, Variable Capacitance Diode – A diode whose AC capacitance varies according to the DC voltage applied.
Light Emitting Diode (LED) – A diode which emits light
LASER Diode – A semiconductor laser
Photodiode – Passes current in proportion to incident light Avalanche Photodiode Photodiode with internal gain
Solar Cell, photovoltaic cell, PV array or panel, produces power from light
Diode for Alternating Current (DIAC, Trigger Diode, SIDAC) – Often used to trigger an SCR
Constant current Diode
Peltier cooler – A semiconductor heat pump


Active components used for amplification.
Bipolar transistors Bipolar Junction Transistor (BJT, or simply “transistor”) – NPN or PNP
Photo transistor – Amplified photodetector
Darlington transistor – NPN or PNP Photo Darlington – Amplified photodetector
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 Silicon Controlled Rectifier (SCR) – Passes current only after triggered by a sufficient control voltage on its gate
TRIode for Alternating Current (TRIAC) – Bidirectional SCR
UniJunction Transistor (UJT)
Programmable UniJunction Transistor (PUT)
Static Induction Transistor/Thyristor (SIT, SITh)
Composite transistors
Insulated Gate Bipolar Transistor (IGBT)

Integrated circuits

Analog Hall effect sensor – Senses a magnetic field
Current sensor – Senses a current through it

Optoelectronic devices
Optoelectronics Opto-Isolator, Opto-Coupler, Photo-Coupler – Photodiode, BJT, JFET, SCR, TRIAC, Zero-crossing TRIAC, Open collector IC, CMOS IC, Solid State Relay (SSR) Opto Switch, Opto Interrupter, Optical Switch, Optical Interrupter, Photo switch, Photo Interrupter LED Display – Seven-segment display, Sixteen-segment display, Dot matrix display

Display technologies
Filament lamp (indicator lamp)
Vacuum fluorescent display (VFD) (preformed characters, 7 segment, starburst)
Cathode ray tube (CRT) (dot matrix scan (e.g. computer monitor), radial scan (e.g. radar), arbitrary scan (e.g. oscilloscope)) (monochrome & colour)
LCD (preformed characters, dot matrix) (passive, TFT) (monochrome, colour) Neon (individual, 7 segment display)
LED (individual, 7 segment display, starburst display, dot matrix)
Flap indicator (numeric, preprinted messages)
Plasma display (dot matrix)

Filament lamp 7 segment display (aka ‘minitron’)
Nixie Tube
Dekatron (aka glow transfer tube)
Magic eye tube indicator
Penetron (a 2 colour see-through CRT)

Vacuum tubes (Valves)

Based on current conduction through a vacuum (see Vacuum tube)
Diode or Rectifier tube
Amplifying tubes
Microwave tubes Klystron
Traveling-wave tube

Optical detectors or emitters

Phototube or Photodiode – tube equivalent of semiconductor photodiode
Photomultiplier tube – Phototube with internal gain
Cathode ray tube (CRT) or Television picture tube
Vacuum fluorescent display (VFD) – Modern non-raster sort of small CRT display
Magic eye tube – Small CRT display used as a tuning meter (obsolete)
X-ray tube – Produces x-rays

Discharge devices

Gas discharge tube


Mercury arc rectifier
Voltage regulator tube
Nixie tube
Thyratron Ignitron


Antennas transmit or receive radio waves
Elemental dipole
Phased array
Loop antenna
Parabolic dish
Log-periodic dipole array

Assemblies, modules

Multiple electronic components assembled in a device that is in itself used as a component
Display devices
Liquid crystal display (LCD)
Digital voltmeters


Prototyping aids

Mechanical accessories

Heat sink

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