Mica and PTFE Capacitors

Part Number	Description / PDF	Quantity
MC18FD221J-TF Cornell Dubilier Electronics	CAP MICA 220PF 5% 500V 1812	0
CD15CD010DO3F Cornell Dubilier Electronics	CAP MICA 1PF 0.5PF 500V RADIAL	3161300
CMR04F181JODM Cornell Dubilier Electronics	CAP MICA 180PF 500V RADIAL	0
CMR04F391FOAM Cornell Dubilier Electronics	CAP MICA 390PF 100V RADIAL	0
CMR08F223GODR Cornell Dubilier Electronics	CAP MICA 22000PF 500V RADIAL	0
CDV30EJ470JO3F Cornell Dubilier Electronics	CAP MICA 47PF 5% 2KV RADIAL	0
CMR06F112GODP Cornell Dubilier Electronics	CAP MICA 1100PF 500V RADIAL	0
CD16FD681JO3F Cornell Dubilier Electronics	CAP MICA 680PF 5% 500V RADIAL	0
CD19FC682FO3F Cornell Dubilier Electronics	CAP MICA 6800PF 1% 300V RADIAL	0
CMR06F821JODM Cornell Dubilier Electronics	CAP MICA 820PF 500V RADIAL	0
CMR05F301JODM Cornell Dubilier Electronics	CAP MICA 300PF 500V RADIAL	0
CM07FD562GO3 Cornell Dubilier Electronics	CAP MICA 5600PF 500V RADIAL	0
CD5EC750GO3 Cornell Dubilier Electronics	CAP MICA 75PF 2% 300V RADIAL	0
CMR07F752JODM Cornell Dubilier Electronics	CAP MICA 7500PF 500V RADIAL	0
CD10ED500JO3 Cornell Dubilier Electronics	CAP MICA 50PF 5% 500V RADIAL	0
CMR08F753JOAP Cornell Dubilier Electronics	CAP MICA 75000PF 100V RADIAL	0
CM06FD112GO3 Cornell Dubilier Electronics	CAP MICA 1100PF 500V RADIAL	0
CD5EC470GO3F Cornell Dubilier Electronics	CAP MICA 47PF 2% 300V RADIAL	0
CD4ED300JO3F Cornell Dubilier Electronics	CAP MICA 30PF 5% 500V RADIAL	0
CMR08F333JODP Cornell Dubilier Electronics	CAP MICA 33000PF 500V RADIAL	0

Mica and PTFE Capacitors

1. Overview

Mica and PTFE (Polytetrafluoroethylene) capacitors are specialized electronic components utilizing mica or PTFE as dielectric materials. Known for exceptional stability, low loss, and high-temperature resistance, they are critical in precision and high-frequency applications. Mica capacitors leverage natural mineral sheets for superior electrical properties, while PTFE capacitors offer excellent chemical resistance and thermal stability up to 200 C.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Mica Capacitors	High Q factor, low leakage current, stable over temperature/humidity	RF tuning circuits, military-grade oscillators
PTFE Film Capacitors	Self-healing properties, high dielectric strength, low moisture absorption	High-frequency power supplies, medical imaging equipment
High-Voltage PTFE Capacitors	Rated >1kV, arc-resistant design	Laser power systems, aerospace ignition modules

3. Structure and Composition

Mica Capacitors: Constructed by sandwiching mica sheets between vacuum-deposited aluminum electrodes. Encapsulated in ceramic or plastic shells with epoxy sealing. PTFE Capacitors: Made by winding PTFE film with metallized electrodes or using stacked foil structures. Terminations use silver epoxy or welded leads for low resistance.

4. Key Technical Specifications

Parameter	Typical Values	Importance
Capacitance Range	1pF-10 F (Mica), 100pF-4.7 F (PTFE)	Determines frequency response and filtering capability
Voltage Rating	50V-10kV	Defines operational safety margin
Temperature Coefficient	5-100ppm/ C	Stability in varying thermal conditions
Dissipation Factor	0.0001-0.002	Energy loss efficiency
Operating Temperature	-55 C to +200 C	Environmental durability

5. Application Areas

Key industries: Telecommunications (RF amplifiers), Aerospace (avionics filters), Medical (MRI gradient coils), Industrial (precision test equipment). Example: 1000V-rated PTFE capacitors in MRI machine deflection coil drivers.

6. Leading Manufacturers and Products

Manufacturer	Product Series	Key Specifications
Murata Manufacturing	NME3 Series	0.1-10nF, 500V, 30ppm/ C
KEMET	C8AK Series	100pF-4.7nF, 1kV, -55 C to +150 C
Vishay Beyschlag	MKP385 Series	1nF-1 F, self-healing, 200 C rating

7. Selection Guidelines

Consider: 1) Required capacitance tolerance (< 1% for critical filters), 2) Voltage derating (use 80% of rating), 3) Temperature extremes (select >20% margin), 4) Mechanical stress (radial vs axial leads), 5) Cost vs lifetime (mica preferred for >10 year deployments).

8. Industry Trends

Emerging trends: Miniaturization for 5G mmWave circuits, hybrid mica-PTFE composites for improved thermal management, and increased adoption in EV charging systems (1500V PTFE capacitors). Market growth projected at 7.2% CAGR (2023-2030) per Grand View Research.