Scl series ● reliability of tantalum capacitors – Samsung SCLSeries User Manual
Page 19
SCL Series
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RELIABILITY OF TANTALUM CAPACITORS
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General
The failure rate of the tantalum capacitor varies with the digression ratio, ambient temperature, circuit
resistance, circuit application, etc.
Therefore, when proper selections are made so as to afford additional margins, higher reliability can
be derived from the tantalum capacitors. Some examples of actual failure rates are presented below
for your reference.
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Failure Rate Calculation Formula
The tantalum capacitors are designed to work at their basic failure
rates shown in Table 3 that prevail when the rated voltage is applied for 1000 hours at 85℃.
Table 3 Basic failure rate
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Failure rate calculation formula
λ
use = λ85 x K
V
x K
R
λ
use : Estimated capacitor failure rate under the operating conditions.
λ
85 : Basic failure rate (Table 3)
K
V : Failure rate correction coefficient by the ambient temperature and derating factor.
K
R : Failure rate correction coefficient by the circuit resistance,
which is the series-connected resistance divided by the voltage applied to the capacitor.
This resistance is connected in series when the power supply side is viewed from the capacitor side.
K
(derating factor)=operating voltage/rated voltage
TYPE
Classification
Basic failure rate
S C E ,SV E
Low E S R type
1% /10 00h
S C M ,S V M
U ltra-M in iaturization Type(060 3)
S C L
Low -p ro file Type
S C S ,SV S
S m all Type
S C N ,S V N
S tanda rd type
P C *
C ondu ctive P olym er Type