Fujitsu 2008 RE Series Lifetime Expectancy free download

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Estimating of Lifetime Functional Polymer Capacitors FPCAP Solid Electrolytic Capacitors with Functional Polymer FPCAP RE Series Calculation formula of lifetime In general, calculation formula of lifetime of capacitors is appeared as follows. FPCAP RE's calculation formula of lifetime is same as usual capacitors. LX = L0 10(T0-TX)/20 Where, LX (Hrs) =Life expectance in actual use L0 (Hrs) =Life time T0 (105 C) =Maximum operating temperature (105 C) TX ( C) =Temperature of capacitor in actual use On the other hand, temperature Tx adds the circumference temperature T as the capacitor temperature and the generating temperature T by ripple current. TX=T+ T T ( C) = Ambient temperature T ( C) = generating temperature Furthermore, the generating temperature T by the ripple current is proportional to ripple current, and is shown by the following formula. When applying the maximum permissible ripple current Io to FPCAP RE, the generating temperature T is about 20 C at inside of capacitor. All large capacitance types of RE serve as this temperature in general. T = ( I / I0 ) 2 T0 I (A rms) = Ripple current in actual use I0 (A rms) = Maximum permissible ripple current T0 ( C) = Generated temperature value by maximum permissible ripple current [About 20 ( C) ] 42 FUJITSU MEDIA DEVICES LIMITED