13.1.3 Understanding diodes

• A diode allows current to flow easily in forward
• Match the semiconductor type with its majority charge carriers:

  p-type ↔️ Holes

  n-type ↔️ Electrons
• What happens to the depletion region in forward bias?

  It reduces
• Arrange the steps in the operation of a diode in forward bias:

  1️⃣ A voltage is applied to the p-type

  2️⃣ Holes are pushed across the junction

  3️⃣ The depletion region reduces

  4️⃣ Current flows easily
• What is the resistance of a diode in forward bias?

  Low resistance
• In forward bias, holes are pushed across the junction by the applied voltage.


  True
• In reverse bias, the widened depletion region blocks the flow of current.
• What is a diode and its basic structure?

  P-n junction semiconductor
• A diode blocks current in the reverse direction.


  True
• When a p-type and n-type semiconductor are joined, a depletion region forms at the junction.
• In reverse bias, the depletion region blocks current flow.


  True
• Match the bias type with its depletion region behavior:

  Forward bias ↔️ Reduced depletion region

  Reverse bias ↔️ Increased depletion region
• In reverse bias, the resistance of a diode is high.
• What happens to the depletion region in reverse bias due to the applied voltage?

  It widens
• What causes the formation of a depletion region in a p-n junction?

  Diffusion of charge carriers
• What happens to the depletion region in reverse bias?

  It widens
• What type of semiconductor is joined in a p-n junction?

  P-type and n-type
• A negative voltage applied to the p-type in reverse bias widens the depletion region.


  True
• What type of voltage is applied to the p-type in forward bias?

  Positive
• In forward bias, high current flow results in low resistance
• The threshold voltage for silicon diodes is typically around 0.7V.


  True
• What are the two regions of the V-I curve of a diode?

  Forward and reverse bias
• In reverse bias, the diode blocks current flow until the breakdown
• What is the voltage range of a rectifier diode?

  Low to medium
• In forward bias, the depletion region is reduced
• In reverse bias, current flow is blocked
• Steps for current flow in forward bias

  1️⃣ External voltage applied to p-type

  2️⃣ Holes are pushed across the junction

  3️⃣ Depletion region is reduced

  4️⃣ Significant current flows easily
• In forward bias, the depletion region is reduced
• What happens to the depletion region in reverse bias?

  It widens
• What two regions are shown in the V-I curve of a diode?

  Forward bias and reverse bias
• In reverse bias, a small current flows until the breakdown
• A forward voltage drop for silicon diodes is typically around 0.6-0.7V.

  True
• Match the diode type with its primary function:

  Rectifier Diode ↔️ Converts AC to DC

  Zener Diode ↔️ Provides stable voltage reference

  LED ↔️ Emits light when forward biased

  Schottky Diode ↔️ High-speed switching

  Varactor Diode ↔️ Functions as variable capacitor
• LEDs typically operate at a voltage range of 1.5V to 3V
• Which diode converts AC to DC?

  Rectifier diode
• Match the diode type with its use case:

  Rectifier Diode ↔️ Power supplies

  Zener Diode ↔️ Voltage regulators

  LED ↔️ Displays

  Schottky Diode ↔️ High-frequency circuits
• Zener diodes are used in voltage regulators to provide a stable voltage reference.


  True
• LEDs emit light when forward biased