Misc Thyristors and Opto Dev

Photovoltaic

Materials that produce a voltage when struck by light.

Phototransistor

a light- sensitive junction that amplifies the base current as the illumination increases.

Photosensitive

Materials that respond to radiant energy, especially light.

Solar cell

Photovoltaic component that produces 0.25.

Radiance

emission of electromagnetic wave from a surface.

Photoemissive

Materials that emit electrons when struck by light.

Photon

A quantum of visible light.

Phototriac output coupler

optoisolator needed for isolated TRIAC triggering.

LED

Photo-source device consisting of PN junction.

Photo FET

A photodetector with the advantage of high input impedance.

Photodetector

Optoelectronic device that detects and conducts light detection.

Photoconductive

Materials whose electrical resistance varies inversely.

Photoresistor

Semiconductors with large minority.

Photosource

Optoelectronic device that performs light emission.

Angstrom

unit of length, measure of displacement equal to 00000000001 meter (10^-10 m)

Darlington Transistor Coupler

Optocoupler type used for increased current capability.

Reverse

photodiodes are normally operated at the _____ region.

Photo-darlington transistor

phototransistor fabricated as Darlington amplifier.

Luminous energy

Emitted energy in the form of photons.

LASCR

A silicon-controlled rectifier operates essentially as ____.

Optoisolator

A light-emitting diode (LED) or infrared-emitting diode (IRED) and a photodiode combined in a single package with a transparent gap between them.

DC current transfer ratio

This parameter is the ratio of the output current to the input current through the LED

Dark current

Reverse photodiode current

Optocoupler

Optoelectronic device that allows interfacing circuits

forward

An LED operates in ____ bias

SBS

Can be triggered into conduction by exceeding the breakover voltage in either direction or by a positive or negative pulse applied to the gate

GCS

positive pulse to the gate triggers it into conduction while a negative pulse to the gate turns it off

GCS

Called a turnoff thyristor, and is similar to an SCR

Shockley

Reverse blocking diode thyristor

SBS

Operates like a SUS, but will conduct in either direction

SBS

V-1 characteristic curve is similar to that of the DIAC, but it has more pronounced "negative resistance" region

SCS

Operates like an SCR, but triggered on by either gate lead

SBS

Have breakover voltages lower than those for DIACs, 8 volts being the most popular rating

SUS

Can be triggered by normal breakover voltage or a positive or negative pulse applied to the gate

False

Radiant energy pertains to the time rate of flow of radiant energy, in ergs or watts per second

True

The first visible red LEDs were produced using gallium arsenide phosphide (GaAsP) on a gaAs substrate

False

Light frequency band ranges from 400,000 750,000 GHz

True

A photometer is used for measuring the intensity of light source

True

Reverse breakdown for a LED is much less than for a silicon rectifier diode

False

In a photoresistor, the minimum resistance when there is no light is termed as light resistance

True

Photometric system is the measurement of spectral emission characteristics of sources of visible light

True

The introduction of gallium nitride made way for the production of blue LEDs

True

a digital output coupler consists of a high-speed detector circuit followed by a transistor buffer stage

True

In a photoresistor, the maximum resistance when there is no light is termed as dark resistance

False

In a photoresistor, when there is incident light, there is only a small thermally generated collector-to-emitter leakage current, called light current

False

Light emission occurs in semiconductor material when photons strike the material and release valence electrons

True

Isolation voltage is the maximum voltage that can exist between the input and output terminals without dielectric breakdown occurring

True

When light strikes the photoresistor, electron-hole carriers are released, hence, the resistance decreases

False

A LASCR output coupler converts an input current variation to an output current variation

False

optoelectronic device data transfer

True

electromagnetic radiation at wavelength somewhat shorter than those of visible light reverse to the ultraviolet band

False

Light detection occurs in semiconductor material when electrons combine with holes.

True

Optoelectronics is a branch of electronics that involves the use of visible light for communications or data-transfer purposes.