Almost all MLCC chip capacitors are mounted to a PCB using a solder reflow process. However, for some harsh environment /automotive applications, another PCB mounting method can be to “glue” them using epoxy adhesive, rather than soldering.
Capacitors designed for use with this epoxy mounting method are NOT compatible with ordinary soldering process; trying to solder them by mistake will cause a failure to properly mount to the board, and if this goes undiagnosed it could lead to false assumptions of malfunctioning or defective parts when the parts are assembled.
Not all MLCC capacitor vendors offer this epoxy mounting option. Digi-Key currently carries 4 manufacturers who offer this option: TDK, Murata, Vishay Vitramon and Knowles.
Unfortunately, there is no unique part numbering scheme for these epoxy-mount capacitors which makes them easy to pick out from solder-type capacitors. Instead, manufacturers usually integrate epoxy mount option into their normal part numbering schemes, which means there’s usually only a single letter in the part number which signifies this important difference. If one isn’t paying attention, this can lead to unfortunate mistakes in defining replacement or second-source capacitors.
- For TDK’s Automotive CGA series, the epoxy mounted parts are designated only by the last letter “D” in the suffix, which is generally defined as “TDK internal code” and can have other letters like “A”, “B”, “C”, “E”, etc
- For Murata’s Automotive GCx series, the epoxy mounted parts are designated only by the 3rd letter in the p/n: “G” and this option even does not mention the term “epoxy”
- For Vishay’s VJ series, there are two different part numbering schemes to be aware of.
The old and obsolete part numbering scheme designated the epoxy option as an “N” option
And their new part numbering scheme designates the epoxy option as “E” or “F”
- For Knowles Novacap, their epoxy mounted parts are designated by “P” (non RoHS) and “PR” (RoHS) in termination code as “Palladium Silver” termination
For TDK, Murata and Vishay parts, Digi-Key is marking the picture of these epoxy mounted capacitor with a special red remark:
Furthermore, there are two options to filter for these epoxy mountable parts, or to filter them out if you don’t want them. To filter for epoxy-mountable parts only, use the “Features” filter in Ceramic Capacitors to identify ‘Epoxy Mountable’, as shown below:
These feature callouts indicate epoxy-mountable parts.
To get rid of epoxy-mounted parts in your searches, use the “Search Within Results” feature of the website and type “~epoxy” before clicking ‘Apply Filters’, as shown below. This is equivalent to a logic search for “NOT Epoxy” and will return any result that does not contain the word ‘epoxy’, culling everything with ‘Epoxy Mountable’ listed as a feature. This method can be used to eliminate any undesirable option from your searches as well.