電容CAP的組成 ppt教材

1、Capacitor IntroductionName: FredDepartment: PowerDate: 2011/03/28Outline: EL-CAPA. 組成B.參數(shù)C. 特性D. 設(shè)計考量E. TransientF. ApplicationG. Layout Issue PL-CAP MLCC ASUS常用料BA+C1C12AL1, ESLL21C1C12BR1, ESRR12 Impedance Z=R + (sC)-1 + sL=R + (jC)-1 + jL s = j=R j(C)-1 + jL=R + jL (C)-1SetXC = (C)-1 , XL = LThen

2、, Z=R + j(XL XC)= R2 + (XL XC)2 # EL-CAP1. 鋁箔鋁箔 (Aluminum Foil)2. 電解液電解液 (Electrolyte)3. 電解紙電解紙 (Electrolytic Paper)4. 導(dǎo)針導(dǎo)針 (Lead)5. 橡膠橡膠 (Rubber)6. 膠管膠管 (Sleeve)a. 組成組成 EL CAP的組成的組成b. 參數(shù)參數(shù) Critical Parameter 容值 (C) Capacitance損失角 (DF) Dissipation FactorTan=R/X=2f C Rf:測定頻率(Hz),C:靜電容量(F),R:等效串聯(lián)電阻( )

3、散逸因數(shù)dissipation factor(DF)存在於所有電容器中，有時DF值會以損失角tan表示。想想，損失角，既有損失，當(dāng)然愈低愈好。塑料電容的損失角很低，但鋁電解電容就相當(dāng)高。DF值是高還是低，就同一品牌、同一系列的電容器來說，與溫度、容量、電壓、頻率都有關(guān)系；當(dāng)容量相同時，耐壓愈高的DF值就愈低。舉實例做說明，同廠牌同系列的10000F電容，耐壓80V的DF值一定比耐壓63V的低。所本刊選用濾波電容常會找較高耐壓者，不是沒有道理。此外溫度愈高DF值愈高，頻率愈高DF值也會愈高。 漏電流(LC)Leakage Current漏電流(leakage current)當(dāng)然要低，它的計算公

4、式大致是:IK CV.漏電流I的單位是A，K是常數(shù),例如是0.01或0.03，每家制造廠會選擇不同的常數(shù)。 C:Nominal Capacitance(uF),V:Rated Voltage(V) 但不論如何，電容器容量愈高，漏電流就愈大。如果你有容量愈大平滑效果愈好的想法，這個漏電流也請考慮在內(nèi)。從計算式可得知額定電壓愈高，漏電流也愈大，因此降低工作電壓亦可降低漏電流。 Note:一般的講一般的講,倉庫裡面的倉庫裡面的E-Cap每每1年都會要求供應(yīng)商年都會要求供應(yīng)商(Supplier)對對 此重新充電此重新充電! 浪湧電壓(SV) Surge Voltagesurge voltage(簡稱S

5、V或Vs)，就是涌浪電壓或崩潰電壓;，超過這個電壓值就保證此電容會被浪淹死小心電容會爆！根據(jù)國際IEC 384-4規(guī)定，低於315V時，Vs=1.15Vr，高於315V時，Vs=1.1Vr。Vs是涌浪電壓，Vr是額定電壓(rated voltage)。 R 11 k o h mR 11 k o h m+V-CO. 紋波電流紋波電流 (Ripple Current) IRipple=* *T T* *A/ESRA/ESR. 電容壽命電容壽命 (Load Life & Shelf Life) Load Life : LX=L0* *2T0-TX/10 Shelf Life :c. 特性特性 EL

6、CAP的特性的特性Note:溫度每升高溫度每升高10,其壽命就會其壽命就會降低降低1倍倍;若溫度每降低若溫度每降低10,其壽命其壽命就會增長就會增長1倍倍. Input CAP application. Output CAP applicationd. 設(shè)計考量設(shè)計考量Capacitor design consider factor.1.Rated ripple current5.ESR Value6.Life ( L=Lo *2exp (105-Ts)/10)2.Capacitance value4.Case size3.Rated voltageEG: Icore=60A,N(phase)

7、=4,Vin=12V,Vcore=1.3V,So Ic,RMS= (60 / 4) * 4 * 0.108 * (1 4 * 0.108) = 7.43A #根據(jù)法拉第與伏秒定理根據(jù)法拉第與伏秒定理.(For buck circuit)= VL(ON) + VL(OFF) = 0If TON = D, TOFF = 1-D , TON + TOFF = TS= VL(ON)*DT + VL(OFF)*(1-D)T = 0= (Vin-Vo)/L * DT - (Vo/L)(1-D)T = 0= (Vin-Vo)/L * DT = (Vo/L)(1-D)T= Vin*D Vo*D = Vo*(1

8、-D)= Vin*D = Vo - Vo*D + Vo*D= Vin*D = Vo = D = Vo/Vin ESR 估算： Vout(ripple) ESR * I （一般（一般Switching 電路要求小於電路要求小於50MV） I : L = (Vin-Vout) D / (I * fs ) Vdynamic Iout*ESRVout*10%e. Transient EL CAP對對Transient之影響之影響 ESR Is Too Bigger Capacitor Value Is Too smaller GNDGSD321VIN+12-12LG21VOGSD321+GNDGNDH

9、GVLHHVL(ON) = Vin-Vo = L(diL/dt)= diL/dt = (Vin-Vo)/LVL(OFF) = -Vo = L(diL/dt)= diL/dt = -Vo/Lf:Application:1.隔直流通交流;2.儲存電荷能量(W=1/2*CV*V*f) etc.g:Layout Guideline(For I/P&O/P Cap)有機半導(dǎo)體鋁固體電解電容器有機半導(dǎo)體鋁固體電解電容器PL-CAPResinAl-canSeparator sheet Organic semiconductorSleeveTapeElementAl-foilAl-bossLeadLeadAl

10、-foilAl-canSeparator sheet with organic semiconductorElementAl-foilAl-tabAl-foilPlastic spacerRubberTerminalTerminalOS-CON的構(gòu)造的構(gòu)造Organic SemiconductorOS-CON有機半導(dǎo)體鋁固體電解電容器有機半導(dǎo)體鋁固體電解電容器1) 容量大容量大電容芯采用卷筒狀鋁箔電容芯采用卷筒狀鋁箔2) 電解質(zhì)導(dǎo)電性高電解質(zhì)導(dǎo)電性高 有機半導(dǎo)體有機半導(dǎo)體(TCNQ復(fù)合鹽復(fù)合鹽) 高分子有機半導(dǎo)體高分子有機半導(dǎo)體(Polythiophene 聚噻吩聚噻吩) 允許紋波電流大允許紋

11、波電流大 耐焊性能高耐焊性能高導(dǎo)電性高導(dǎo)電性高 = Lower ESR電容器類型電解質(zhì)類型導(dǎo)電性(mS/cm)非固體電解電容器Electrolyte solution（電解液）3固體電解電容器Manganese dioxide（二氧化錳）30OS-CONOrganic semiconductor (TCNQ復(fù)合鹽復(fù)合鹽)300Conductive polymer（高分子有高分子有機半導(dǎo)體機半導(dǎo)體）3000OS-CON的的電氣特性電氣特性O(shè)S-CON的的電氣特性電氣特性損耗損耗 = I = I 2 2 x x ESRESR發(fā)熱發(fā)熱00.511.522.533.5Ripple CurrentArm

12、s33uF/16V47uF/16V100uF/16V220uF/16VOS-CON (SVP series)OS-CON (SA series)Al-E. (Low Impedance)Ta. (Low Impedance)OS-CON的可靠性的可靠性O(shè)S-CON的應(yīng)用的應(yīng)用AL-E 680uF3PVoutIL 1A/divVinVoutIL 1A/divVinOS-CON 4SVP100M1POS-CON有機半導(dǎo)體鋁固體電解電容器有機半導(dǎo)體鋁固體電解電容器主要特點主要特點! OS-CON 的的 ESR低低 阻抗值低阻抗值低/ /允許紋波電流大允許紋波電流大 適合用于通信產(chǎn)品的電源模塊輸出濾波

13、適合用于通信產(chǎn)品的電源模塊輸出濾波 線路板的電源輸入口濾波線路板的電源輸入口濾波 ! OS-CON 的的 ESR基本上不受溫度的影響基本上不受溫度的影響 特別適合用于有低溫功能的通信產(chǎn)品（基站等）特別適合用于有低溫功能的通信產(chǎn)品（基站等）! OS-CON 的壽命長的壽命長 65時計算上可以達到時計算上可以達到200,000 小時（約小時（約 22年）年） ! OS-CON 有極性但耐反向電壓有極性但耐反向電壓MLCC MLCC ( Multi-layer Ceramic Capacitor ) 積層陶瓷電容積層陶瓷電容BASIC FOR MLCC 1. Structure(結(jié)構(gòu)結(jié)構(gòu)) 2. F

14、ormula（計算公式） 3. Characteristic (特性) 4. Tolerance of different material (不同材質(zhì)的參數(shù)差別) 5. Life （壽命） 6. Real Application (實際應(yīng)用)PS:MLCC-Process Flow- Chart漿料製備瓷膜成型印刷積層均壓成型切割去膠燒結(jié)滾磨角端銅端電極燒附電鍍測試包裝10V,0805,Y5V,4.7UF,+80/-20%DC Bias Characteristic-100-80-60-40-2000246810DC Bias Voltage V C/C %Temperature Chara

15、cteristic-100-80-60-40-20020-50-250255075100Temp. C/C %20321122110TTeVVttt2: effectual lifet1: test timeT1:test temperature(Spec)T2:working temperatureV1:test voltage(Spec)V2:working voltage 5.LifeFor ExamplePutting 10 pcs of ceramic CAPs. in chamber do the life time test with accelerated method, th

16、e failure mode is defined as when the capacitance exceed its rated value (-5%), as can be seen in the figure.When the applied voltage is two times of its rated voltage, and the operation temperature is 85C. The life time is calculated as following. 20321122110TTeVVttThe figure illustrates t1=5000hr,

17、 T1=105C.yearshret94. 15 .16987102150002085105326.Real ApplicationBy passBy passSnubberBoost cap(A)Basic Structure for bootsrapePVCCGSD321Cboot12Rboot12Phase+12VCgs12Driver12Low_sideBEC123BCE123GSD321Rgate12High_sideWhen Low_side onHigh_side1. PVCC charge Cboot through Rboot to ground2. The Cgs of m

18、osfet discharge through Rgate So the falling-time of MOSFET depend on Rgate.PVCCGSD321Cboot12Rboot12Phase+12VCgs12Driver12Low_side23BCE123GSD321Rgate12BEC3When high_side on Cboot 通過Rboot&Rgate 給High_side MOSFET Cgs充電。 所以Rboot+Rgate 越大，MOS的開通速度越慢， Rboot+Rgate 越小，MOS的開通速度越快。PVCCGSD321Cboot12Rboot12Phase+12VCgs12Driver12Low_side23BCE123GSD321Rgate12High_sideBEC3(B)Snubber Circuit Analysis修改前修改前修改後修改後PCB LayoutLow Side MosfetSn