GRT188R60J226ME13D & VJ0805G226MXYTW1BC – The Benefits of MLCC Capacitors Part II
As discussed last week, MLCC capacitors will provide a variety of benefits to designers willing to use them
As discussed last week, MLCC capacitors will provide a variety of benefits to designers willing to use them. However, recent developments have shown stock levels to become critical. The trade press and analysts are assuming that the situation will remain in a similar state for the foreseeable future. Fortunately, designers can react to this with a variety of behaviours.
Let us start out with the obvious one
Electrolytic capacitors have improved a lot during the last few years. The problems seen on Danaher’s Tektronix TDS5xx/7xx series of oscilloscopes or in Boeschert power supplies will happen only if you use extraordinarily low quality parts. If your application allows it, using a low ESR electrolytic capacitor is a nice way to stay clear of the entire MLCC conundrum.
Should the larger weight or cost of electrolytic capacitors be unacceptable, going with the flow is an attractive choice. Companies such as Vishay, who are specialized on the automotive market, usually tend to be less squeezed than their consumer-oriented competitors. For example, a GRT188R60J226ME13D currently has a lead time of 36 weeks, while the VJ0805G226MXYTW1BC is available more easily (20 weeks).
Smaller is better
Reputable German sources claim that Murata switched their manufacturing equipment away from classic case sizes such as 0805 or 1206, and instead prefer smaller ones such as 0402. From a person looking at raw materials, this decision makes good sense; the smaller the capacitor, the smaller the amount of rare earths required for its fabrication.
If your entire manufacturing takes place using pick and place machines, no significant action is required. Simply open your favorite EDA program, and reduce the size of the component footprints. 0603 size chips can be soldered by hand with good magnification.
Finally, the big question remains; should you stockpile parts, or should you not? Let’s start out with the obvious; with a tool such as OEMsecrets, your trawling net is significantly wider than that of the normal developer who is trying to source components from one or two distributors by hand.
This, however, does not mean that it does not make sense to stockpile parts. If your customer is willing to pay you for it, acting as a commis can be highly profitable. Having a stockpile of a few thousand components is helpful also in that you can send them off later using the broker such as Kruse. On the other hand, most stockpiling operations fail for two reasons. First of all, companies tend to overfill their stocks anticipating demand which never crops up. Problem number two is the often insufficient quality of the stock-holding facilities – if you store capacitors wrongly, they might still be usable, but will be refused by reputable third-party stock resellers.