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Difficulty: MediumTransistors

Match each transistor terminal lead with its primary operational function in solid-state circuits.

  • BJT BaseSupplies the small input control current that regulates the main current flow
  • BJT EmitterInjects the primary charge carriers into the middle semiconductor region
  • BJT CollectorGathers majority charge carriers to route output current through the load
  • FET GateApplies an electrostatic field to modulate channel conductivity without drawing steady DC input current

Answer

BJT Base pairs with 'Supplies the small input control current that regulates the main current flow'; BJT Emitter pairs with 'Injects the primary charge carriers into the middle semiconductor region'; BJT Collector pairs with 'Gathers majority charge carriers to route output current through the load'; FET Gate pairs with 'Applies an electrostatic field to modulate channel conductivity without drawing steady DC input current'.
In bipolar junction transistors, the base regulates the conduction pathway through a small input current, the emitter emits/injects majority charge carriers, and the collector gathers those carriers to deliver current to the load. In field-effect transistors, the gate acts as an electrostatic control terminal that modulates channel conduction via voltage without drawing significant steady-state current.

Step-by-Step Solution

1
Determine the control and injection roles of BJT leads
The base acts as the control terminal requiring current, and the emitter supplies the charge carriers.
Bipolar junction transistors are current-driven devices where a small base current forward-biases the base-emitter junction to release carriers from the emitter.
2
Determine the output gathering role of the BJT collector
The collector collects carriers that successfully pass through the thin base layer.
The collector is physically designed with a larger area and reverse bias to capture carriers and handle heat dissipation from load current.
3
Determine the voltage-control role of the FET gate lead
The gate regulates current through an electrostatic field without drawing steady current.
Field-effect transistors have extremely high input impedance at the gate, relying on voltage rather than current to modulate channel resistance.

Key Concept

Transistor Terminal Functions and Operating Mechanisms
Estimated Time:1m 0s
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Topics

Transistors

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