What are glass capacitors? 

Glass capacitors refer to specialised capacitor devices, which are particularly designed with three basic elements; a glass dielectric, aluminium electrodes, and an encapsulation. The glass capacitors are named so because of their typical glass dielectric materials. They are specifically used in RF, or radio-frequency, circuits that demand extreme and ultimate performance. 

Applications

Due to their higher performance capabilities, glass capacitors can be found in a wide range of applications. They are usually used as specialist components under special conditions. As such their applications include:

• Circuits that remain exposed to extreme temperature conditions, for example remote sensors.
• Devices that require a high Q circuit, for example oscillators.
• Circuits that have low microphone requirements, for example in PLL synthesisers.
• Applications that demand high power amplifiers, for example RF power amplifiers.

Importance of glass capacitors

Glass capacitors, possessing a glass body as the dielectric material, are extremely important specialist components of electronic circuits. They not only offer higher levels of performance but also pack in a number of other benefits like low-temperature coefficient, high tolerance, and precision as well. 

The capacitance value of glass capacitors is relatively low, varying between a fraction of a picofarad and a thousand picofarads. Their high performance properties make them ideal capacitors for appliances where other capacitors cannot be used. For instance, glass capacitors are extremely important for radio frequency (RF) circuits.