There are two types of mica capacitors: clamped mica capacitors and silver mica capacitors. Clamped mica capacitors are now considered obsolete due to their inferior characteristics. Silver mica capacitors are used instead. They are made by sandwiching mica sheets coated with metal on both sides.
The main features of mica types of capacitors are: High precision - up to 1% of the rated capacitance value. High stability - these capacitors are very stable, hardly degrade over time, and the assembly is protected by epoxy resin. High tolerance to temperature. High tolerance to voltage (up to 1kV). High tolerance to frequency.
Mica capacitors can withstand high voltages, operate at high temperatures and have low leakage current. Because mica capacitors have a very small inductive characteristic and low losses, they are often used in radio frequency (RF) circuits. Silver is used to form mica capacitor plates.
This is because silver mica capacitors have much better characteristics than clamped mica capacitors. Definition – A mica capacitor uses mica as the internal dielectric. Mica capacitors come in two different types: clamped and silver mica capacitors. They are extremely stable components and have low resistive and inductive losses.
These components are reliable, stable, and high precision which is available from different ranges like low to high voltage, and mica capacitor capacitance range is from 20 pF – 10 µF. Mica capacitors are applicable where low capacitance & high accuracy changes over time are required.
The applications of the mica capacitor include the following. Silver mica capacitors are used in power RF circuits where stability is extremely important. These capacitors are used in tuned circuits with high frequency like oscillators and filters. Sometimes, they are utilized in snubbers.