L火线N零线色环电阻的识别方法:棕1,红2,橙3,黄4,绿5,蓝6,紫7,灰8,白9,黑0,这是色环电阻的代表数字。4环电阻,一二位数值位,第3位为倍率(什么颜色就是10的几次方),第4位为误差位。5环电阻,一二三位数值位,第4位为倍率,第5位为误差位。四环色环电阻的误差:只有”金“、”银“,金表示5%,银表示10%。五环色环电阻的误差:棕表示1%,红表示2%,灰表示0.05%,白表示环保电阻,绿表示0.5%,蓝表示0.25%,紫表示0.1%,金表示5%,银表示10%例如,4环电阻表示10K电阻,综黑橙金(10*10的3次方,5%误差)4环电阻表示10K电阻,综黑黑红棕(100*10的2次方,1%误差)数字电阻的表示方法为:最后一位数表示倍率,而前几位为数值位。滤波电容的选择:经验公式:C=(3~5)×(T/2)÷RR:输出电压与最大输出电流的比值。T:为交流电周期。电容降压后的电流计算应按容抗来计算既:Xc=1/(ωC)=1/(2πfC)常见涤纶电容器耐压的标注是采用一个数字和一个字母组合而成。数字表示10的幂指数,字母表示数值,单位是V(伏)。字母=数值A=1.0B=1.25C=1.6D=2.0E=2.5F=3.15G=4.0H=5.0J=6.3K=8.0Z=9.0例如:2A代表1.0*100=100V(即1.0乘以10的2次冥)1J代表6.3*10=63V常用三极管型号结构耗散功率(mW)Pcm集电极电流Max(mA)Icm集电极-基极电压(V)集电极-发射极电压发射极-基极电压(V)引脚排列放大系数hfeVcbo(V)VceoVebo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型号结构耗散功率(mW)Pcm集电极电流Max(mA)Icm集电极-基极电压(V)Vcbo集电极-发射极电压(V)Vceo发射极-基极电压(V)Vebo引脚排列放大系数hfeC1674NPN2502030204EBCC1815NPN40015060505ECBC2001NPN60070030255ECBC2060NPN75070040325ECBC2229NPN800502001505ECBC2230NPN8001002001605ECBC2236NPN900150030305ECBC2271NP9001003003006ECBNC2383NPN90010001601606ECBC2482NPN9001003003007ECB2N3904NPN35020060406EBC2N5551NPN3506001801606EBCS8050NPN1000150040256EBC8050SNPN62550040205EBC9011NPN4003050305EBC9013NPN62550040205EBC9014NPN45010050455EBC9016NPN4002530204EBC9018NPN4005030155EBC3DD13001NPN12002006004007BCE8~40MJE13001NPN70003005004009ECB(to-92)8~40MJE13002NPN120010006004007BCE10~40MJE13003NPN4000020007004009BCE5~403DD13005NPN7500040007004009BCEMJE13005NPN7500050007004009BCEMJE13006NPN8000080006003009BCE5~60MJE1300NP8000080007004009BCE7NMJE13008NPN100000120006003009BCE6~40MJE13009NPN100000120007004009BCE6~40型号结构耗散功率(mW)Pcm集电极电流Max(mA)Icm集电极-基极电压(V)Vcbo集电极-发射极电压(V)Vceo发射极-基极电压(V)Vebo引脚排列放大系数hfe