Charcroft Capacitors

High reliable mica capacitors with radial leads and multiple dipcoating ensuring high mechanical strength and excellent climatic performance. Careful selection of all raw materials and constant monitoring of processes and equipment ensures an overall uniform level of quality required by the stringent requirements of professional and military equipments. Charcroft DM capacitors offer long term stability, close tolerance, small temperature coefficient of capacitance, and minimum losses (high Q factor). They have been designed for the following applications: logic and transmission circuits, pulse forming networks, delay lines, filters, d.c. voltage blocking, timing circuits, high reliable electronic instruments for flight electronics, measuring and test devices, navigation etc. The different sizes are in accordance with MIL Styles DM10, DM15, DM19, DM20, DM30 and DM42.

Moulded Radial

Moulded radial capacitors are provided with stand-off feet to ensure stability during flow soldering, and to prevent moisture traps between the components and the PCB. In addition, flux vapours have plenty of space to escape, preventing blow holes in the soldered joints.

Miniature Resin Moulded Radial

Charcroft miniature moulded capacitors have been designed for PCB application when space is a premium. All units have been designed with a nominal 5.0mm minimum spacing and can be supplied on tape and reel for automatic insertion if required.

The Charcroft miniature moulded range and the Mil Styles DME 10 and DME 15 have been designed such that they can be packaged on tape and reel for automatic insertion.

Manufactured from superior quality mica plates with fire-on silver electrodes, Charcroft Mica Capacitors have fully bonded plates which are further reinforced by edge-bonding. Terminal wires are securely soldered to the reinforced area with a high melting-point solder. To provide a high degree of humidity and mechanical protection, all capacitors are encapsulated in thermo-setting resin, or high temperature thermoplastic.

These are specially designed and manufactured to our own unique specification to ensure safe handling, installation and use in equipment. Solder-coated copper-wire terminations are incorporated in all Charcroft silvered Mica requirements to meet the robustness of termination requirements of BS 2011.

The encapsulation and coding materials used in the manufacture of mica capacitors are specially selected to withstand the solvents commonly employed for cleaning and flux removal in PCB applications.

Radial and Axial (MIL Style)

All Charcroft silvered mica capacitors are, as their name implies, manufactured on a base dielectric of mica. As an inert inorganic natural material which is as old as the earth itself, mica provides circuit designers with the highly desirable quality of long-term stability. Temperature changes in terms of ppm/ºC are small. For precise figures, see individual capacitor type sections.

Boxed Radial

The CS12 has a low loss Mica dielectric, making it suitable for use in equipment such as transmitter filters which involve high alternating voltages, high frequencies andhigh currents. The internal construction of the capacitor ensures that the rated voltage is well below the voltage where ionisation discharges occur. A very small change in Mica capacitance with temperature ensures that the capacitance remains within the stated tolerance over the entire working temperature range. Internal heating is also minimal in this capacitor due to the very low dielectric losses of Mica and the controlled thickness of silver electrodes.

All capacitors are encapsulated in thermo setting resin to provide excellent humidity and mechanical protection. In addition these devices are moulded with 'stand-off' feet to ensure flux vapours escape and stability is ensured during flow soldering. The encapsulation and coding materials have been specially selected to ensure they are not affected by solvents commonly used for cleaning and flux removal on PCB's. Terminations are tin coated copper wire and meet the requirements of BS2011 robustness of termination.

Product Documentation

Data Sheet (PDF)

These capacitors are specially designed for audio applications. Constructed from the finest Indian Ruby Mica plates, they are cut by hand, then have silver electrodes printed on. The plates are stacked to the required value, have their edges reinforced with silver paste and are then sintered at 560°C. After firing they are cut into individual chips ready for lead attachment. To enhance their audio properties, solid silver lead wires are attached before final trimming and dipping in epoxy resin. These Capacitors are fully assembled and individually trimmed by hand in our UK based manufacturing facility.

Product Documentation

Data Sheet (PDF)

These capacitors are specially designed for use with transmitter filters of up to 1kW power output. Any capacitance value can be supplied within the range stated below in 1pF steps. Capacitance tolerance is ±1pF up 100pF and ±1% above. Capacitors are designed to operate at RF and will run cool under normal transmitting conditions. All materials used in their construction are non ferrous therefore minimising inductive effects and subsequent heating of capacitors and other components in close proximity.

Product Documentation

SBH Dipped Radial Capacitors Datasheets | PDF

The SB1 and SBA108 capacitors have a low loss dielectric, making it suitable for use in equipment such as transmitter filters which involve high alternating voltages, high frequencies and high currents. The internal construction of the capacitor ensures that the rated voltage is well below the voltages where ionisation discharges occur.



A very small change in mica capacitance with temperature ensures that the capacitance remains within the stated tolerance over the entire working temperature range.

Product Documentation

SB1 & SBA108 HV/HF Capacitors Datasheets | PDF

Terminations are tin coated copper wire and meet the requirements of BS2011 robustness of terminations. All capacitors are encapsulated in Thermo setting resin to provide excellent humidity and mechanical protection. In addition these devices are moulded with 'stand-off feet to ensure flux vapours escape and stability is ensured during flow soldering. The encapsulation and coding materials have been specially selected to ensure they are not affected by solvents commonly used for cleaning and flux removal on PCB's.

Product Documentation

Radial Moulded Silver Mica Capacitors Datasheets | PDF

These capacitors are encapsulated in silicone rubber and designed to operate at high temperatures, a very small change in mica capacitance with temperature ensures that the capacitance remains within the stated tolerance over the entire working temperature range.

Product Documentation

A3M-HT & SM1-HT High Temp Capacitors Datasheets | PDF