For a long time Murata technical staff have urged everyone to replace tantalum capacitors with ceramics - the bigger with smaller, the palladium with base metal. The current world shortages of tantalum capacitors and medium-sized MLCCs have confirmed the value of this advice.
Sceptics could be forgiven for thinking that, in a highly competitive market, Murata was simply trying to steal a march on the competition. In fact, as one of the world's big users as well as makers of components, it has a vested interest in having reasonable supplies of suitable components available to all.
Two of the most volatile markets worldwide are those for tantalum and palladium. In both cases, sources are restricted and subject to wild escalation in times of shortage.
Tantalum has long been the beast of the capacitor world. The attraction being that it could provide very high C/V per unit volume. However, availability has become a problem, again. Reliability and performance are relatively poor compared with ceramic and, as an oxygen-getter when heated, tantalum can be a fire hazard. Not for nothing did some defence contractors ban some types of tantalum capacitor when they were an essential part of current production.
Technically, palladium has played a noble role in the evolution of today's subminiature components. It has provided a reliable bridge between the high-firing temperatures of yesteryear and today's expanding lower-firing materials. As operating frequencies rise the conductivity of electrodes becomes more critical. The move from palladium has introduced readily available higher conductivity materials and this has improved performance as well as stabilised costs to some extent.
While all this has been happening, miniaturisation has come on apace. Material technology has given higher values and performance than ever before while allowing the replacement of other dielectrics with lower values that give the same circuit performance. Where palladium must still be used, a move to smaller sizes cuts the cost for all concerned.
To conclude, the tribulations of tantalum, palladium and oversized components can be substantially resolved with new, proven, Murata materials and processes. So it is never too late; if it is too big, too lossy, too expensive or too hard to get, ditch tantalum, ditch palladium, downsize and contact Murata for good advice.
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