标题: PCB?è?????é??????[×???]
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论坛元老会



UID 10
精华 6
积分 240
帖子 260
阅读权限 10
注册 2004-2-7
状态 离线
发表于 2004-2-9 11:03  资料  个人空间  短消息  加为好友 
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,????????PCB?è???±???è????×??????????×?????????????ù°????????????ü?à?????????????????????×????????×??í?????ú?????????????ü???????????????·?????×?????????????±????????±????????????????×???????????????????????????ü????×ê?×(drill)???????¨plating?????¤???????????????×??????×ê?×?è?¨·????±?????¤?????????×?????????????????±?×??????????×ê?×?±????6±??±??????·¨±??¤?×±????ù????????±??????????????????é6??PCB°????????¨?¨?×????????50Mil×ó?????ù??PCB?§?????á????×ê?×?±??×???????????8Mil??

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C=1.41??TD1/(D2-D1)
???×?????ú?????á?????·?ì?????÷???°?ì?????¤?????????????±?????????????·?????????????????????????é??????50Mil??PCB°?????????????????10Mil???????±????20Mil?????×???????????????????à????32Mil,?ò?????????¨?????????????ü?????????×?????ú?????ó??????C=1.41x4.4x0.050x0.020/(0.032-0.020)=0.517pF??????·????????????????±??±?????????T10-90=2.2C(Z0/2)=2.2x0.517x(55/2)=31.28ps ?????????????????????????????????×?????ú????????????????±??????§?????????÷????????????×??????à?????????×?????????????????è???????????÷??????????

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L=5.08h[ln(4h/d)+1]
????L?????×????????h?????×???¤????d??????×ê?×???±???????????????????????×???±???????????°?ì???????????????°?ì×??ó???????×???¤????????????????????×????????????????×??????????L=5.08x0.050[ln(4x0.050/0.010)+1]=1.015nH ?????????????????±????1ns???????????§×è???ó??????XL=??L/T10-90=3.19???????ù??×è?????????????÷???¨????????????±?????????±???×????????·?????????????????????????±?ò?è???¨?????????×?????ù???×?????ú???????á??±???????

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1??    ????±?????????????·????????????????í?????????×?ó????±?????6-10??????
?????éPCB?è????????????10/20Mil?¨×ê?×/???????????×??????????????????????????????°?×?????????????????8/18Mil?????×?????°?????????????????????ü???????????×?????????????ò?????????×?ò???????????????ó????????????×è????
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