Design and specifi cations are subject to change without notice Ask factory for technical specifi cations before purchase and or use Whenever a doubt about safety arises from this product please contact us immediately for technical consultation

Description

Niveau: Supérieur, Doctorat, Bac+8
Design and specifi cations are subject to change without notice. Ask factory for technical specifi cations before purchase and/or use. Whenever a doubt about safety arises from this product, please contact us immediately for technical consultation. Aluminum Electrolytic Capacitors Application Guidelines 1. Circuit Design Ensure tha t operational and mounting condit ions follow the specified conditions detailed in the catalog and specification sheets. 1.1 Operating Temperature and Frequency Elect ro ly t ic capac i tor e lec t r ica l parameters are normally specified at 20°C temperature and 120Hz frequency. These parameters vary with changes in tempera t u r e and f r equency. C i r cu i t des igne rs should take these changes into consideration. (1) Effects of operat ing temperature on electr ical parameters a)At h igher temperatures, leakage current and capac i tance increase while equivalent series resistance(ESR) decreases. b)At lower tempera tures, leakage current and capac i tance decrease while equivalent series resistance(ESR) increases. (2) Effects of frequency on e lect r ica l parameters a ) A t h i g h e r f r e q u e n c i e s , c a p a c i t a n c e a n d impedance decrease while tan ? increases. b)At lower frequencies, r ipple current generated heat will r ise due to an increase in equivalent series resistance (ESR).

• failure


• capacitor


• circuit board


• relief vent


• leakage current


• capacitors


• avoid using


• dc voltage


• can cause

Sujets

• Failure
• Capacitor
• Printed circuit board
• Leakage

Informations

• Publié par: profil-zyak-2012
• Nombre de lectures: 19
• Langue: English

Extrait

 ApplicationGuidelines

1. Circuit Design E n s u r et h a to p e r a t i o n a la n dm o u n t i n gc o n d i t i o n s follow the specified conditions detailed in the catalog and specification sheets. 1.1 Operating Temperature and Frequency E l e c t r o l y t i cc a p a c i t o re l e c t r i c a lp a r a m e t e r sa r e nor mallyspecified at 20°C temperature and 120Hz frequency. These pa ra m e t e r svar ywith changes in t e m p e r a t u r ea n df r e q u e n c y.C i r c u i td e s i g n e r s should take these changes intoconsideration. (1) Ef fe c t so fo p e r a t i n gt e m p e r a t u r eo ne l e c t r i c a l  parameters  a) A th i g h e rt e m p e r a t u r e s , l e a k a g ec u r r e n ta n d  ca p a c i t a n c ei n c r e a s ewhile equivalent series  resistance(ESR)decreases.  b)At lo w e rt e m p e r a t u r e s ,l e a k a g ec u r r e n ta n d  ca p a c i t a n c edecrease while equivalent series  resistance(ESR)increases. (2) Effects of fre q u e n c yon el e c t r i c a lp a r a m e t e r s  a) A th i g h e rf r e q u e n c i e s ,c a p a c i t a n c ea n d  impedancedecrease while tanδ increases.  b)Atlower fr e q u e n c i e s,r ipplecurrent generated  heatwill ri s ed u et oa nincrease in equivalent  series resistance(ESR).

Aluminum Electrolytic Capacitors

1.2 Operating Temperature and Life Expectancy (1) Expected life is affected by operating temperature.  Ge n e r a l l y,e a c h1 0°C ri ne d u c t i o nt e m p e ra t u r e  willdouble the expected life.Use capacitors at  th el o w e s tp o s s i b l et e m p e r a t u r eb e l o wt h e  maximumguaranteed temperature. (2 )I fo p e r a t i n gc o n d i t i o n se x c e e dt h em a x i m u m  gu a r a n t e e dl i m i t ,r a p i de I e c t r i c a lp a r a m e t e r  deteriorationwill occur, and irreversible damage  willresult.  Checkfor maximum capacitor operating tempera-  tu r e si n c l u d i n ga m b i e n tt e m p e r a t u r e ,i n t e r n a l  capacitortemperature rise caused by ripplecurrent,  an dt h ee f f e c t so fr a d i a t e dh e a tf r o mp o w e r transistors, IC'sor resistors.  Avoidplacing components which could conduct  heatto the capacitor from the back side of the circuit  board.  (3)The formula for calculating expected Iife at lower  operatingtemperatures is as follows;

T 1 - T 2 10 L 2 = L 1 where,x 2

 L 1 : Guaranteed life (h) at temperature, T 1 °C  L 2 : Expected life (h) at temperature,T 2 °C  T 1 : Maximum operating temperature (°C) T 2 : Actual operating temperature, ambient  temperature+ temperature rise due to  ripplecurrent heating(°C)  Aquick reference capacitor guide for estimating  expectedlife is included for your reference.

■Expected Life Estimate Quick Reference Guide 120 1. 85°C2000h 2.105°C1000h 110 2 3 4 3.105°C2000h 100 4.105°C5000h 90 1 80 70 60 50 40 2000500010,00020,00050,000100,000200,000 (h) 24h operat- 12345720 ion Years 3610152030 8h/d Years

■Failure rate curve

Initial failure period Random failure period

Life Time

Time

Wear failure period

Design and specifications are subject to change without notice. Ask factory for technical specifications before purchase and/or use. Whenever a doubt about safety arises from this product, please contact us immediately for technical consultation.