What are mica and PTFE capacitors?

Mica and PTFE capacitors are capacitor devices typically featuring thin sheets of mica or Polytetrafluoroethylene (PTFE) as the dielectric material. The sheets of mica usually have a coating of deposited metal as well as a layer of epoxy, the latter to protect against environmental elements.

Mica and PTFE capacitors provide optimum stability and hence are ideal for applications that require high stability, reliability and precision. As such, they are commonly used in high-frequency applications. 

Types

Mica and PTFE capacitors are available in a wide range of varieties, each differing in specifications like the voltage, capacitance range, factor, etc. These include:

• Standard dipped mica capacitors 
• Reel packed dipped mica capacitors 
• Miniature dipped mica capacitors 
• High reliability dipped mica capacitors 
• High voltage mica capacitors 
• SMT multilayer PTFE capacitors 
• High frequency dipped mica capacitors

Applications

These capacitors are used extensively across different electronic applications. They are usually found in:

• High voltage inverter circuits 
• Coupling circuits 
• Telecommunications equipment
• Cable TVs
• Radio transmitters 
• Medical equipment
• Defence electronics 
• Aerospace equipment