Electronic Fundamentals

388. Diodes are:

• a) Conductors,
• b) Semi-conductors
• c) Insulators

389. For the intrinsic conductivity of diodes

• a) At 0 degrees Kelvin, a semiconductor is a non-conductor
• b) At 0 degrees Celsius, a semiconductor is a non-conductor
• c) At 0 degrees Kelvin, a semiconductor is a conductor

390. A junction diode

• a) Is similar to a vacuum diode but cannot rectify
• b) Has one p-n junction
• c) Can handle only very small currents

391. In a semiconductor junction diode, electrons are the minority carriers.

• a) Within the P region
• b) Within the N region
• c) In both the N and P regions

392. Forward voltage of a silicon diode is.

• a) 1.7V
• b) 0.7V
• c) 0.3V

393. To function, i.e. conduct, a junction diode made of silicon requires a forward bias of at least

• a) 0.2 V
• b) 1.41 V
• c) 1 V

394. If forward bias is increased from zero on a p-n junction, a rapid increase in current flow for a relatively small increase in voltage occurs.

• a) When the flow of minority carriers is sufficient to cause an avalanche breakdown
• b) When the depletion layer becomes larger than the space charge area
• c) Only after the forward bias exceeds the potential barrier

395. When a diode is forward biased the

• a) Positive lead is connected to both N and P type
• b) Positive lead is connected to the P type and negative to the N type.
• c) Positive lead is connected to the N type and negative to the P type

396. The micro diodes are:

• a) Primarily used for electrical power supply devices
• b) Mainly used in communication technology
• c) Used in rectifier circuits for large power outputs

397. The rectifier diodes are:

• a) Primarily used for electrical power supply devices
• b) Mainly used in communication technology
• c) Used in rectifier circuits for large power outputs