MLCC life

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Life of MLCC
The life of MLCC is largely dependent on operating voltage and temperature. The factor of
temperature (ambient temperature and internal heating due to ripple current) is the most critical to
the life of MLCC.
General formula to estimate lifetime:
The lifetime of MLCC is generally expressed by using two elements representing the effects of
voltage acceleration and temperature acceleration, which is shown by the following equation:
LX=L0 / (AV×AT) or LX=L0．KT．KV
Where: LX = Lifetime of MLCC to be estimated
L0 = Base lifetime of MLCC
AV = Voltage acceleration term, and AV=(Applied voltage / Guarantee voltage) n=(VX/VG) n
n ≒ 3.
AT = Temperature acceleration term, and AT=2 (Ambient temperature – Acceleration temperature)/10
=2(Tx – To)/10
KT=2 (Acceleration temperature –Ambient temperature)/10=2(To – Tx)/10 = 1/AT.
KV=(Guarantee voltage / Applied voltage) n=(VG/VX) n = 1/AV
For example:
The material is Murata’s GRM31CR71A106K01L (1206, X7R, 10uF, 10V)
The applied voltage is 12.6V.
The ambient temperature is 85℃.
To get the guarantee voltage is 20V for 1000 ±12 hours at the maximum operating temperature ±
3℃ from the datasheet of GRM31CR71A106K01L.
The acceleration temperature is 125℃ that is X7R specification.
AV= (12.6/20) 3=0.25, AT=2 (85-125)/10= 1/16.

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