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Zorluk: ZorTransistors

An electronics technician is analyzing solid-state switching and amplification circuits. Match each transistor operating region to its corresponding junction biasing condition and functional circuit behavior.

  • BJT Cutoff RegionBoth the base-emitter and base-collector junctions are reverse-biased, resulting in negligible current conduction and acting as an open switch.
  • BJT Saturation RegionBoth the base-emitter and base-collector junctions are forward-biased, causing maximum current flow with minimum collector-emitter voltage drop and acting as a closed switch.
  • BJT Forward-Active RegionThe base-emitter junction is forward-biased while the base-collector junction is reverse-biased, allowing base current to linearly control a larger collector current.
  • JFET Ohmic (Linear) RegionThe gate-source depletion region leaves the channel unpinched at low drain-to-source voltages, allowing the channel to function as a voltage-controlled variable resistor.

Cevap

BJT Cutoff matches both junctions reverse-biased (open switch); BJT Saturation matches both junctions forward-biased (closed switch); BJT Forward-Active matches forward-biased base-emitter and reverse-biased base-collector (linear amplification); JFET Ohmic Region matches unpinched channel at low drain voltage (voltage-controlled resistor).
Transistor states are governed by internal PN junction bias levels and gate field controls: Cutoff has both BJT junctions reverse-biased (acting as an open switch), Saturation has both BJT junctions forward-biased (acting as a closed switch), Forward-Active utilizes a forward-biased base-emitter and reverse-biased base-collector junction for linear amplification, and the JFET Ohmic region operates prior to pinch-off as a voltage-controlled variable resistor.

Adım Adım Çözüm

1
Determine the junction bias conditions for digital BJT switching states.
Cutoff requires reverse-biasing both the base-emitter and base-collector junctions (open switch), while saturation requires forward-biasing both junctions (closed switch).
Biasing conditions control whether carrier flow is completely blocked or fully saturated across the semiconductor junctions.
2
Determine the junction bias conditions for BJT linear amplification.
Forward-active operation requires the base-emitter junction to be forward-biased (VBE≈0.7 VV_{BE} \approx 0.7\text{ V}) and the base-collector junction to be reverse-biased.
This asymmetric bias configuration allows a small base current to modulate a substantially larger collector current proportionally.
3
Analyze the operational characteristics of a field-effect transistor below pinch-off.
In the ohmic (triode) region, the drain voltage is lower than the pinch-off threshold, so the channel acts as an electric-field-controlled resistor.
The gate-to-source voltage alters depletion layer width, varying the cross-sectional conductive area and resistance of the channel.

Anahtar Kavram

Transistor Operating States, Biasing Rules, and Terminal Relationships
Tahmini Süre:1m 30s
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