电解电容纹波及寿命测试方法.doc

【精品文档】如有侵权，请联系网站删除，仅供学习与交流电解电容纹波及寿命测试方法.精品文档.Electrolytic Capacitor Ripple Current Derating Test Method and Life Time Evaluation From：郭雪松 Date：Oct-27-04一SPEC1.电解电容零件工程规格书中之Standard Rating表格，其中规定了不同规格的电解电容Rated Ripple Current值，例如：Sharp机种PWPC C904(滤波电容) 67L215L-820-15N (CNN公司 KXG Series)VDCVCap.uFCase sizeD*Lmmtan L.C.uARated Ripple CurrentmA rms/1051min5min120Hz100KHz4508218*35.50.24157676371517852.此电容用于电源输入端滤波，因此采用120Hz时的Rated Ripple Current规格715mA。3.而用于评估电解电容Ripple Current之Spec要依据以下公式：SPEC=Spec（component）×频率系数（FM）×温度系数（TM） 注：FM/TM取值方法见附表4.OTPV 评估电解电容Ripple Current的Derating规格为85，因此 测试值<SPEC×85 时判定OK。二Test Method将电解电容接地端吸开串联一导线，直接用电流计探头测试该导线电流的有效值（rms），测试时要调整输入电压值（90V264V）达到纹波电流最大。见图示： Irms三附表（FM&TM取值方法）：NCC公司产品为例1.Multiplying Factors on KMG Series（radial lead type） Frequency MultipliersRange50Hz120Hz300Hz1KHz10KHz100KHz3.3uF0.651.001.351.752.302.504.7uF33uF0.751.001.251.501.751.8047uF1000uF0.801.001.151.301.401.502200uF0.851.001.031.051.081.08 Temperature MultipliersTemp（）55657585105Multipliers2.232.2321.7312. Multiplying Factors on KY SeriesFrequency MultipliersRange120Hz1KHz10KHz100KHz180uF0.400.750.901.00220uF560uF0.500.850.941.00680uF1800uF0.600.870.951.002200uF3900uF0.750.900.951.004700uF0.850.950.981.00 Temperature MultipliersTemp（）55657585105Multipliers2.232.2321.7313. Multiplying Factors on KXG Series Frequency MultipliersRange120Hz1KHz10KHz100KHz100uF1.001.752.252.5120uF1.001.671.752.25Temperature MultipliersTemp（）55657585105Multipliers2.232.2321.731*Temperature multipliers shows the guide limits of the maximum available ripple current at each of the temperature,of which the life time at the rated maximum operating temperature is expected.四电解电容寿命评估测试方法1.Calculation Formula: 电容寿命Life Time= Life(spec) ×2(Ts-Tt)/10 Life(spec)：指spec中标明的寿命值 Ts：电容最高使用温度值 Tt：电容本体温度测试值2.判定方法：以上计算得出之寿命值与整机MTBF目标值比较，若大于目标值则判定OK。3.例如：SHARP机种C904 Life（spec）10000Hrs，Ts105，Tt52.6，。SHARP MTBF目标50000Hrs。 Life Time10000×2(105-52.6)/10=377917Hrs>50000Hrs OK