Definition

1. Noun:
   • A type of electronic component: A triode is a specific kind of thermionic vacuum tube containing three essential electrodes: a cathode, an anode (or plate), and a control grid. Its primary function is to amplify electrical signals by using small voltage changes on the grid to control a larger current flow from the cathode to the anode.

Examples of Usage

• Noun:
  • The early radio receivers often used a triode for signal amplification.
  • Lee De Forest's invention of the triode was a pivotal moment in electronics.
  • In this circuit, the triode is configured as a common-cathode amplifier.

Advanced Usage

• "Triode region": In modern electronics, this term is also used analogously to describe a specific operating mode of field-effect transistors (FETs), where they function similarly to a triode vacuum tube by acting as a voltage-controlled resistor.
  • The MOSFET operates in the triode region when used as a switch.

Variants and Related Words

• Diode (n): A vacuum tube or semiconductor device with two electrodes.
• Tetrode (n): A vacuum tube with four electrodes.
• Pentode (n): A vacuum tube with five electrodes.
• Triode is also the base for the adjective triodic, though this is a highly specialized technical term.

Synonyms

• Amplifying tube: A general term for vacuum tubes used for amplification, which includes triodes.
• Valve (British English): A common term for a vacuum tube, which can be a triode.

Related Idioms or Phrases

(This word is a highly technical term and is not commonly used in idiomatic expressions.)

Noun

1. a thermionic vacuum tube having three electrodes; fluctuations of the charge on the grid control the flow from cathode to anode which makes amplification possible