Definition

1. Noun:
   • A semiconductor device with two terminals, allowing current to flow primarily in one direction: A diode is a fundamental electronic component that acts as a one-way valve for electric current. It is typically made from semiconductor materials like silicon and has a positive (p-type) and a negative (n-type) region, forming a p-n junction.
   • A thermionic tube (valve) with two electrodes, used as a rectifier: In older electronics, a diode can also refer to a vacuum tube containing two electrodes (a cathode and an anode), which similarly allows current to flow in only one direction.

Usage Examples

• Noun:
  • A light-emitting diode (LED) is a common type of diode that produces light when current passes through it.
  • The circuit uses a diode to convert alternating current (AC) to direct current (DC).
  • The engineer tested the diode to ensure it was not allowing reverse current flow.

Advanced Usage

• "Forward bias": A condition where voltage is applied to a diode in the direction that allows current to flow easily.
  • When the diode is in forward bias, it has a low resistance.
• "Reverse bias": A condition where voltage is applied to a diode in the direction that blocks current flow.
  • In reverse bias, only a tiny leakage current flows through the diode.
• "Breakdown voltage": The reverse voltage at which a diode begins to conduct current in the wrong direction, which can damage it.
  • Exceeding the diode's breakdown voltage will cause it to fail.

Variants and Related Words

• LED (Light-Emitting Diode) (n): A diode that emits light when electrically biased in the forward direction.
  • The LED indicator on the device shows it is powered on.
• Zener diode (n): A special type of diode designed to allow current to flow backwards when a specific reverse voltage (Zener voltage) is reached, used for voltage regulation.
  • A Zener diode is used in the circuit to maintain a constant output voltage.
• Rectifier (n): A device (often using one or more diodes) that converts AC to DC.
  • The power supply contains a bridge rectifier made of four diodes.

Synonyms

• Rectifier: A device that converts alternating current to direct current (this is a function of a diode).
• Semiconductor device: A broader category of electronic components, including diodes.

Related Phrases

• Diode bridge: A configuration of four diodes in a bridge circuit to achieve full-wave rectification of AC.
  • The diode bridge efficiently converts the AC input to a smoother DC output.
• Diode logic: A simple form of digital logic circuit constructed from diodes.
  • Early computers sometimes used diode logic for basic gating functions.

Noun

1. a semiconductor that consists of a p-n junction
2. a thermionic tube having two electrodes; used as a rectifier