High-voltage discharges, known as surface arcing, arc-overs, flash-overs or corona discharges, can cause interference and component failure by producing a visible spark in addition to electrical noise.

Factors such as humidity, solder balls, flux residue and other contaminants can all contribute to surface-arcing, particularly in MLCCs with higher dielectric constant materials. The layout of the PCB can also increase susceptibility through the use of oversize pads, vias beneath capacitors, buried layers or geometries which prevent effective cleaning.

ProtectiCap™ provides consistent performance advantages with a special coating applied to an optimised high-voltage MLCC. This produces a smooth, sealed finish which allows higher voltages and capacitance values to be achieved in smaller case sizes.

Comprehensive testing has shown an improvement in performance of a minimum of 1000V over standard parts. Standard test methods were based on international specifications including AEC-Q200, IECQ-IECC and MIL standards.

ProtectiCap™ performance comparison

Maximum test voltage before arcing in bulk tests across the range of sizes

HIGH VOLTAGE CAPACITOR RANGE EXTENSION

Developments in ceramics materials and manufacturing technology have led to significant extensions in Syfer's High Voltage multilayer capacitor range, in some case meaning a doubling of capacitance, or more. For example, a 1206 1.5kV capacitor was available up to 2.7nF, but has now been increased to 10nF, and an 1812 1kV has been extended from 56nF to 100nF. Syfer now offers the highest capacitance values in the world for most 500Vdc and higher MLCCs in the following case sizes:

This also may allow the possibility of choosing a smaller case size, which would result in reduced cost and less board area required. For example a 1206Y1K00102KXT is now available in a an 0805 case size, and an 1812Y1K00103KXT is now offered in a 1206 case size. The table below gives further examples:

Typical applications for these high voltage applications include power supplies, dc-dc converters, telecoms, military and aerospace.

For added reliability, Syfer offers its FlexiCap™ polymer termination option, as an alternative to a standard plated termination. FlexiCap™ accommodates a greater degree of board flex than a conventional termination. To meet the most stringent quality standards, Syfer can also offer additional testing services

Syfer (Syfer Technology Ltd) - Low Voltage Capacitor Range Extension

A breakthrough in low fire ceramic chip manufacture has enabled Syfer to launch its highest capacitance devices ever. Increased capacitance values are available in the 16V, 25V and 50/63V series of multilayer chip capacitors. A brand new 10V range has also been launched, based on X5R dielectric.

Capacitance has more than doubled in most devices in these ranges for the C0G/NP0 dielectric. For the new 10V range, parts in the C0G dielectric range from a 0603 device with 392nF capacitance to a 564nF part in a 2225 footprint.

Similarly dramatic improvements in capacitance have been achieved with the X7R dielectric. A typical device, such as the 0805 footprint 16V part, now features an impressive 680nF capacitance, more than double the 330nF available previously.

In addition, Syfer has introduced an X5R dielectric, in voltages from 10V to 53/65V and packages from 0603 to 2225, typically providing increased capacitance over their X7R counterparts. However, it should be noted that these parts are only specified to 85°C, while the X7R range is qualified up to 125°C.

The key advantage of low fire capacitors over those produced using a high fire process, is reliability. For industry sectors such as medical, automotive, military & aerospace and industrial control, ruggedness and reliability are critical. Typically the low fire process produces a more structurally stable component body, with a higher dielectric constant, a lower volt per micron rating, and reduced capacitance loss.

For added reliability, Syfer offers its FlexiCap TM polymer termination option, as an alternative to a standard plated termination. Flexicap accommodates a greater degree of board flex than a conventional termination. To meet the most stringent quality standards, Syfer can also offer additional testing services.

Syfer (Syfer Technology Ltd) - High Voltage Capacitor Range Extension

New Development
We are delighted to tell you about an exciting new development in our high voltage MLCC range. Advances in ceramics materials a nd manufacturing technology have led to significant extensions in our chip range, in some case meaning a doubling of capacitance, or more. For example, a 1206 1.5kV capacitor was available up to 2.7nF, but has now been increased to 10nF, and an 1812 1kV has been extended from 56nF to 100nF.

Highest Capacitance Values
The table below shows how much the values have been increased for the 500V to 1.5kV ranges, and in most instances none of our competitors can offer higher capacitance values. This enhances our reputation as a leader in high voltage capacitor technology.

Smaller case size option
One of the benefits of the higher values is that it may be possible to offer the customer the same capacitance and voltage in a smaller case size, and so providing space and cost savings. The following table gives some examples.

Syfer (Syfer Technology Ltd) - High Voltage MLCCs for LCD Inverter Applications

Development
Syfer Technology has developed a range of surface mount multilayer ceramic capacitors aimed specifically at the LCD inverter market. The advantage gained over standard product is a reduced susceptibility to surface arcing which allows for the replacement of leaded components. The improved properties are achieved by the utililisation of a unique C0G/NP0 dielectric material.

Parts for these applications are identified with the suffix code FB9. Users should also carefully consider solder pad design as this can influence arcing voltage.

Capacitance Ranges

Ordering Information

Syfer (Syfer Technology Ltd) - Panel Mount EMI Power Filters

As part of our product range extensions we are now able to offer filters for power applications where high current ratings are required. Utilising plastic film technology, which offers the advantage of being self-healing, the range includes high ac and dc working voltage options along with parts designed and tested to meet the rigorous demands of EN132400/EN60950 safety specifications.

Typical applications include IT servers, telecoms base stations, MRI room equipment, power supplies, radar and military vehicles. Filters designed and tested to meet EN132400/EN60950 class Y2 and Y4 requirements are intended for use on mains supply systems or lower voltage lines where safety is important.

Current ratings up to 100A are available, with voltages up to either 600Vdc or 250Vac, and maximum capacitance value is 40μF. Higher current ratings can be achieved, and it is possible to provide custom multiway assemblies which can make assembly simpler and reduce cost.