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Difficulty: MediumTransistors

Electronic systems utilize various solid-state semiconductor transistors tailored for specific switching, amplification, and sensing applications. Match each transistor type to its defining operating principle and physical characteristic.

  • Bipolar Junction Transistor (BJT)A current-controlled component requiring a small input base current where charge carriers consist of both electrons and holes
  • Junction Field-Effect Transistor (JFET)A voltage-controlled device utilizing a reverse-biased PN junction to modulate channel conductivity
  • Metal-Oxide-Semiconductor FET (MOSFET)An insulated-gate device offering extremely high input impedance that controls conduction via an electric field across a dielectric oxide layer
  • PhototransistorAn optoelectronic component that converts incident light into an amplified collector current at an exposed semiconductor junction

Answer

Bipolar Junction Transistor (BJT) pairs with the current-controlled device using both electron and hole carriers; Junction Field-Effect Transistor (JFET) pairs with the voltage-controlled device using a reverse-biased PN junction; Metal-Oxide-Semiconductor FET (MOSFET) pairs with the insulated-gate component featuring high input impedance and an oxide dielectric; Phototransistor pairs with the optoelectronic component converting incident light into amplified collector current.
Each semiconductor device corresponds uniquely to its operating physics: BJTs are bipolar current-controlled devices; JFETs utilize reverse-biased PN junctions for channel modulation; MOSFETs employ an insulated dielectric gate for field-effect control; and phototransistors utilize optical stimulation to generate base-region carriers.

Step-by-Step Solution

1
Identify the carrier conduction and control mechanism of the BJT
The BJT is a current-controlled bipolar device relying on both majority and minority carriers (electrons and holes).
The term bipolar explicitly indicates the participation of both carrier polarities, controlled by base current.
2
Differentiate between the field-effect transistor junction types (JFET vs. MOSFET)
The JFET relies on a direct reverse-biased PN gate junction, while the MOSFET incorporates an insulated oxide layer that eliminates DC gate current entirely.
The metal-oxide insulator in a MOSFET provides near-infinite input impedance compared to the reverse-biased PN junction of a JFET.
3
Distinguish the optoelectronic sensor category (Phototransistor)
The phototransistor operates by replacing or augmenting electrical base current with photon-generated charge carriers.
Light striking the transparent casing generates electron-hole pairs at the junction to initiate conduction.

Key Concept

Classification, control mechanisms, and structural properties of major transistor families
Estimated Time:1m 0s
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Topics

Transistors

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