Mica and PTFE Capacitors

Part Number	Description / PDF	Quantity
CMR03E330JOAP Cornell Dubilier Electronics	CAP MICA 33PF 100V RADIAL	0
CM04FC271JO3 Cornell Dubilier Electronics	CAP MICA 270PF 300V RADIAL	0
MC12EF180J-F Cornell Dubilier Electronics	CAP MICA 18PF 5% 1KV 1210	0
CMR05F221JODM Cornell Dubilier Electronics	CAP MICA 220PF 500V RADIAL	0
CD7FA911FO3 Cornell Dubilier Electronics	CAP MICA 910PF 1% 100V RADIAL	0
CD4FD121GO3F Cornell Dubilier Electronics	CAP MICA 120PF 2% 500V RADIAL	0
CM06FD162FO3 Cornell Dubilier Electronics	CAP MICA 1600PF 500V RADIAL	0
CD15FD161GO3F Cornell Dubilier Electronics	CAP MICA 160PF 2% 500V RADIAL	0
MC12FA301J-TF Cornell Dubilier Electronics	CAP MICA 300PF 5% 100V 1210	0
CD10FA391FO3 Cornell Dubilier Electronics	CAP MICA 390PF 1% 100V RADIAL	0
MIN02-002DC560J-F Cornell Dubilier Electronics	CAP MICA 56PF 5% 300V SMD	400
CD17CD040DO3 Cornell Dubilier Electronics	CAP MICA 4PF 0.5PF 500V RADIAL	0
MC22FF751J-F Cornell Dubilier Electronics	CAP MICA 750PF 5% 1KV 2220	0
CMR04E390JODP Cornell Dubilier Electronics	CAP MICA 39PF 500V RADIAL	0
CMR08F433GODR Cornell Dubilier Electronics	CAP MICA 43000PF 500V RADIAL	0
CMR04E750JODM Cornell Dubilier Electronics	CAP MICA 75PF 500V RADIAL	0
CMR06F392GODM Cornell Dubilier Electronics	CAP MICA 3900PF 500V RADIAL	0
MC12FA121G-F Cornell Dubilier Electronics	CAP MICA 120PF 2% 100V 1210	7000
CMR03F391JOYP Cornell Dubilier Electronics	CAP MICA 390PF 50V RADIAL	0
CMR05E270JODR Cornell Dubilier Electronics	CAP MICA 27PF 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.