A series of recent high-voltage multilayer ceramic capacitor (MLCC) technology breakthroughs at Vishay have resulted in a new range of surface-mount MLCCs that are better suited for the ballast application than any previous type of capacitor. These new HVArc® Guard capacitors are presently available with NP0 and X7R dielectrics and voltage ratings currently offered from 250 V to 1000 VDC.
MLCCs used in lighting ballast circuits can be exposed to high voltages, over 1000 VDC in air. The capacitors are prone to both surface-arc-over and internal breakdown. In either event, failure may result when surface arc-over causes the circuit to be de-stabilized, which may in turn cause damage to surrounding components even if the capacitor remains temporarily functional. The unique HVArc Guard capacitor design prevents arc-over while allowing the use of smaller case sizes in lighting ballast applications.
Until now, MLCCs in the larger 1210, 1808 and 1812 cases have been used in high-voltage lighting ballast applications. New HVArc Guard high-voltage MLCCs can replace many of these standard high voltage capacitors in ballast circuits, allowing more compact designs while reducing component cost.