Datasheet

16© KEMET Electronics Corporation • KEMET Tower • One East Broward Boulevard T2005_T491 • 3/11/2019
Fort Lauderdale, FL 33301 USA • 954-766-2800 • www.kemet.com
16
Tantalum Surface Mount Capacitors – Standard Tantalum
T491 Industrial Grade MnO
2
Soldering Process
The KEMET families of surface mount capacitors are
compatible with wave (single or dual), convection, IR, or vapor
phasereowtechniques.Preheatingofthesecomponents
is recommended to avoid extreme thermal stress. KEMET's
recommendedproleconditionsforconvectionandIR
reowreecttheproleconditionsoftheIPC/J-STD-020D
standard for moisture sensitivity testing. The devices can
safelywithstandamaximumofthreereowpassesatthese
conditions.
Please note that although the X/7343–43 case size can
withstandwavesoldering,thetallprole(4.3mmmaximum)
dictates care in wave process development.
Hand soldering should be performed with care due to the
dicultyinprocesscontrol.Ifperformed,careshouldbe
taken to avoid contact of the soldering iron to the molded
case. The iron should be used to heat the solder pad, applying
solderbetweenthepadandthetermination,untilreow
occurs.Oncereowoccurs,theironshouldberemoved
immediately. “Wiping” the edges of a chip and heating the top
surface is not recommended.
Duringtypicalreowoperations,aslightdarkeningofthe
gold-colored epoxy may be observed. This slight darkening is
normal and not harmful to the product. Marking permanency
is not affected by this change.
Prole Feature SnPb Assembly
Pb-Free Assembly
Preheat/Soak
Temperature Minimum (T
Smin
) 100°C 150°C
Temperature Maximum (T
Smax
) 150°C 200°C
Time (t
s
) from T
smin
to T
smax
) 60 – 120 seconds 60 – 120 seconds
Ramp-up Rate (T
L
to T
P
) 3°C/secondmaximum 3°C/secondmaximum
Liquidous Temperature (T
L
) 183°C 217°C
Time Above Liquidous (t
L
) 60 – 150 seconds 60 – 150 seconds
Peak Temperature (T
P
)
220°C*
235°C**
250°C*
260°C**
Timewithin5°CofMaximum
Peak Temperature (t
P
)
20 seconds maximum 30 seconds maximum
Ramp-down Rate (T
P
to T
L
) 6°C/secondmaximum 6°C/secondmaximum
Time25°CtoPeak
Temperature
6 minutes maximum 8 minutes maximum
Note: All temperatures refer to the center of the package, measured on the
package body surface that is facing up during assembly reow.
* For Case Size height > 2.5 mm
** For Case Size height ≤ 2.5 mm
Storage
Tantalum chip capacitors should be stored in normal working environments. While the chips themselves are quite robust in
other environments, solderability will be degraded by exposure to high temperatures, high humidity, corrosive atmospheres,
and long term storage. In addition, packaging materials will be degraded by high temperature – reels may soften or warp
andtapepeelforcemayincrease.KEMETrecommendsthatmaximumstoragetemperaturenotexceed40°Candmaximum
storagehumiditynotexceed60%relativehumidity.Temperatureuctuationsshouldbeminimizedtoavoidcondensation
on the parts and atmospheres should be free of chlorine and sulphur bearing compounds. For optimized solderability, chip
stock should be used promptly, preferably within three years of receipt.
Time
Temperature
T
smin
25
T
smax
T
L
T
P
Maximum Ramp-up Rate = 3°C/second
Maximum Ramp-down Rate = 6°C/second
t
P
t
L
t
s
25°C to Peak