T498_1 Datasheet, PDF (1/3 Pages) Kemet Corporation – Product Update - T498 High Temperature (+150) Tantalum SMT Capacitors

Product Update – T498 High Temperature (+150°C) Tantalum SMT Capacitors
KEMET Electronics Corp. P. O. Box 5928 Greenville, SC 29606 [phone] www.kemet.com
The tantalum SMT capacitor in its solid-state structure
is typically rated as capable of 125°C applications. The
T498 tantalum surface mount capacitor has a maximum
temperature rating of 150°C. The difference between the
T498 and the standard tantalum capacitors lies within its
material set and design. The materials changed include the
carbon, the silver epoxy, the silver paint, the plastic
molded encapsulant, and the leadframe. These materials
still contain no lead and are fully RoHS¹ compliant. The
standard finish on the leadframe is a matte tin plating over
nickel, and the device is capable of the 260°C reflow pro-
files as defined in J-STD-020C². A gold or tin-lead finish
is also available.
dot matrix pattern. The effect does not create a coloration
change, but creates a surface abrasion as the laser removes
the reflectivity of the plastic surface in the desired pattern.
Figure 2. Photograph of “D” case, T498 SMT capacitors.
Through oblique lighting and vision systems, the mark-
ings can be quite revealing as shown in Figure 2. An ex-
planation for the pattern with the markings is shown in
Figure 3.
Figure 1. Structure of new T498 tantalum capacitor.
The appearance of this device is radically different
from the previous SMT tantalum capacitors from KEMET,
in that the color is no longer gold with brown lettering.
The gold material has a heat activation of color change
from yellowish gold to brown created in the presence of a
controlled surface temperature rise. A laser flash through
a mask is used to create the polarity and identifying marks
on the gold plastic. Using this material and process in the
presence of higher heats created an effect where the entire
surface of the package was turning brown, and the mark-
ings became indiscernible.
The black compound has no discernable change in col-
oration when exposed to extended temperatures above
125°C. The marking on the package for the polarity stripe,
capacitance code, voltage rating, the KEMET logo, and the
print week code (PWC) are still created with a laser in a
Figure 3. Component marking diagram for T498 capacitor.
©2005 KEMET Electronics Corp.
May 2005