Deck 47: Light Emitting Diodes and Photodiodes

Question 1

The basic light-emitting diode is formed by joining gallium arsenide (GaAs) or ____________________ (GaP).

Answer 1

gallium phosphide

Question 2

When electrons in the N-type material are combined with holes in the ____ material, energy is released in the form of photons.

A) energy gap
B) GaAsP
C) P-type
D) GaAs

Answer 2

C

Question 3

Light-emitting diodes (LEDs) are among the most common devices found in the electrical\electronics field.

Answer 3

True

Question 4

How can you produce white LEDs?

Question 5

Light-emitting-diodes can be tested in a manner similar to that of testing a(n) ____________________ diode.

Question 6

First introduced in 1962, early LEDs emitted high-intensity red light and were used as indicator lights for many years.

Question 7

Briefly describe photodiodes.

Question 8

Junction diodes have a forward voltage drop of about ____ volt for silicon and 0.4 volt for germanium.

A) 0.5
B) 0.6
C) 0.7
D) 0.8