HIGH VOLTAGE CERAMIC CAPACITORS BASED ON BRAND NEW DIELECTRIC MATERIAL
Exxelia presents a new range of C48X high voltage ceramic capacitors. No more compromises between stability and capacitance! The brand new C48X material combines most advantages of NPO and X7R dielectrics, enabling the new high power and high frequency ceramic capacitor range to provide great stabil...
No more compromises between stability and capacitance! The brand new C48X material combines most advantages of NPO and X7R dielectrics, enabling the new high power and high frequency ceramic capacitor range to provide great stability in voltage, high capacitance, great dissipation factor and fast charge/discharge.
Miniaturization is a driving need for future electronics pieces of equipment. This evolution, true whatever the application, leads Exxelia Technologies (ex-Eurofarad) to develop a brand new high voltage ceramic capacitors range based on a new dielectric material named C48X, combining most of the advantages of NPO and X7R dielectrics.
Compared to X7R material, C48X dielectric allows to get the same capacitance values under working voltage with the unrivaled advantage of a very low dissipation factor (less than 5.10-4). Besides, it can also withstand very high dV/dt, up to 10kV/μs, which makes it the solution of choice for pulse and fast charge/discharge applications. Thus capacitors with C48X dielectric appear to be ideally suited for power applications where heat dissipation may be detrimental to performances and reliability.
Exxelia Technologies’ capacitors based on the C48X material have been developed from 200V to 5kV with chip sizes ranging from 1812 to 16080, allowing a maximum capacitance value of 10μF 200V (10 times more than with an NPO ceramic). The standard stacked versions are proposed with a maximum capacitance value of 47μF 200V.
Regarding the mounting of these capacitors, many configurations are possible to be compatible either with surface mounting or through-hole mounting. All these versions can be suitable for space use and can be designed in order to avoid any whisker growth risk (10% min lead in all tin-lead alloys used). The introduction of the C48X range in the EPPL (European Space Agency Preferred Parts List) for space is in progress for sizes 0603 to 6560 from 100V to 1kV up to size 1210 and up to 5kV until the size 6560).
Some typical applications:
• 400Hz Aircraft
• Precision/filtering capacitance in thermally challenged environment for AC or DC voltage
ESA QPL Film capacitors
PM907S and PM948S are full series of Polyester Film Capacitors. PM907S products are suitable for voltages from 50V up to 1250V and offer capacitance values from 82nF up to 180μF. PM948S can be used with a voltages from 50V up to 630V with capacitance values from 22nF up to 47μF. Both series can support extreme conditions with temperatures from -55°C to +125°C, and offer high energy density, low ESR & ESL and high RMS current. Typical characteristics Self-healing properties Open circuit failure mode High reliability & quality High energy density Very light masse Low ESR & ESL
NEW INVAR TUNING ELEMENTS WITH SELF-LOCKING SYSTEM
Working frequencies in Space applications are shifting to Ka, Ku or even Q band, while cavity filters are undergoing the general trend towards miniaturization: this context calls for a much more precise and stable tuning element now offered by Exxelia Temex, daughter company of Exxelia, through their last innovative and unrivalled solution to incorporate a self-locking system into their Invar Tuning Elements. Invar-36 is a unique Iron-Nickel alloy (64 % Fe / 36 % Ni) sought-after for its very low coefficient of thermal expansion. With 1.1 ppm. K–1 between 0°C and 100°C, Invar-36 is about 17 times more stable than Brass which is the most traditional and common alloy Tuning Elements are made of. The working temperature range in Space is so wide that this property becomes essential for a reliable and stable cavity filter tuning. Self-locking system is a technology commonly used on Tuning Element made of Brass or other soft “easy-to-machine” alloys but is innovative and pretty advanced when applied to hard and tough Invar 36. The design consists of two threaded segments separated by two parallel slots. After cutting both parallel slots, the rotor is compressed in its length in order to create a plastic deformation. Thus, an offset is induced between the two threaded segments which generates a constant tensile stress in the rotor from the moment threaded segments are screwed.