TVS????????±????è±?ESD±??¤????????
?????±?? : 2004?ê01??17??
±??????è±???ESD±??¤??·?????????TVS??????????????·????§??±??¤?÷?????????ü?÷???à±??????????????????????????±???±??????????±??¤???ó???????÷?????ò?????????????????????????????÷???ù???????????÷?????ó??±??¤????????????????×????à??????????±????°?÷???ú?ú?????????è???????±???????????í??PCB??????±????é????±??????è±???ESD±??¤??????????TVS???????÷????

±??????è±???±???±??????????ú??PDA??MP3??·??÷??????????·±?????????????×????????·???(ESD)?????÷????????????????????±??¤?÷?????????á?ì???ú?÷?????????¨???ò?????????ü?????é?????é?????·???????ò???????§?ó???????ú?·???????????????ó????????

??°??é???????????à?è±?±??????????????????????????????????ó????·?????±??¤?????ü??????????????????????I/O????????????±????¨????ESD±ê×???IEC61000-4-2??????????????????????????????·??§??2kV??15kV(????·???)??·??????÷×?????20A/ns???????????????±????????60ns???????ù?????????ù?ú?ú??????×???????????°???????????????×??????????????÷????

±??????è±??ù??????IC?÷???ó?à???????????????????ú?·???????????¤?¤?????è?§??????·???±????ò???ü?×?÷??????????20V×ó?????á????????????????±??¤·?·¨????????±é?????????????????á?ì?????è±?????????????

TVS????????????

??????±??????è±???ESD±??¤?÷???????à???????è?????±????·????÷?????¨±??¤???·????????±????è±??????????????¨???°±??????·×?????????·?·¨??????±??ü???????????÷???ù???ú???à?????????????÷???????????????????????????????§??????·??¤???ü?????????°±í???÷????????TVS???????????à????????????±í???????????????????ó????????

TVS??????×???????????????·??????????????±???????????????·?ò?÷???ì?????????°??±????§????????????????????±????????ü?????????????????????????·?·?????í????TVS???????è?????????????????ü?????????÷???á???????ò???????í?????????????·?????????÷?±???ü?í????????±í??(??1)??

TVS????????????

TVS?????????????????????????????????à±???TVS??????P/N?á?????ü?ó???????á????????????TVS?????ü?????????????????????±?????????????????????ò??????±??¤?????è±????¤×÷???????·??°????????ü???§????

TVS???????????????à?è?????±????????±í???ù×°??????????×÷ESD±??¤??????±????????è???ò±????????à?÷??????????????????±???????5kV?????÷?á?ì????10%?????????§?§????10kV?±????????????60%????TVS????????15kV?????????????è±???????????????????????????·±???????÷??????±???????????????8kV???????÷(IEC61000-4-2±ê×?)??????????TVS???????§±??¤×????ú?·??????????

TVS??MLV???à?????????????á???÷??(MLV)?????????????§?????±???????÷?????????à?÷??????·?????????-???÷(×è??±í??)??????????????????×?????????????2??3±??????????????????????????????????????·???÷????±??¤???????????·????TVS???????????ü?????????????ò×?(??2)?????±?????????????????????????????????è±???????????·??????????ò?????????????á?°?ì???????????ì???§???ò????????TVS?????????÷??±í??·?×°?ù?????÷????×°???????ó???????????á??±??????????ü??????????EMI??RFI????±??¤?????????§?????÷????±????????????è????

?í????????????????????????????????·?±????????ü?÷???????????????????????????à??EMI??????RFI·??¤????????TVS?????????????÷?????????????è???ù???????÷????????????±?????????±???PCB°????????±?×??·???°é?ú×?????

TVS?à??????

???í???±???????÷????????×???°ì·¨???????±???÷???????÷????????TVS???????????·°???????±?±??¤???·?????????±???±???????????·?????¤×÷?????ó??TVS??????±?·??ú??±????á???????±???÷??????????×è?¨?·?????á???????±???÷?¨????????±???????±???±?±??¤?÷???????????????????????????°??±?±??¤???·???±±??????????????±???±?????á?????ó??TVS??????×?????????×è×????????????·???????????????í?à?÷?????????à?????÷?ó?????????°?????á·??ú????±????????????¤×÷?????¨·??§???????????????á·??ú?????ò????????

??????????????????????????TVS???????±??±???×?????????????????????(??3)??

1???????ú×?IEC61000-4-2?ú??±ê×???TVS??????±??????????????í×???8kV(????)??15kV(????)??ESD???÷??????°??????ú?ú?§????×??????ú?·?????????ü?????????÷±ê×????????????????????ó??±????è±????????è????????°??è???????÷????
2??Vwm????????????????×????±???????????????????????ó??????±?±??¤???·???????¤×÷??????·??ò???????á???????????·?????????ü???è????????±?±??¤???·???????¤×÷???????ü?????ù?????á??TVS?¤×÷???°?????????·??????????????
3??Vc????????????????×????á??????????????????ESD???÷×????±?¨??TVS?????????ü?????ó??±?±??¤???·??????????????????·??ò?÷??????±?????????????
4??Pppm???¨???????? ?????ù??×??ó?????????????±??·??????????÷???????????è±?????°?????500W??TVS??×???????
5??????????????/?????????????????·???????????????????·?????????ó?????????ù?ò???????????????ò???è???ù?????·???????????¨?ù???÷????????·??§?????????·??°?????????????????(??LCTVS????????TVS?????????ó??3pF)?????????????ó?????????·??????????????40pF??

????·?±??é???????????????è±?ESD±??¤??TVS?????ó??

????????/?????????????·??????????±??????????÷???????????ó????????100pF×ó???????????????????????è???????ú?ú???ó??·????????????????ò??·??????·???°?????é?????????????·TVS?????ó?????é?????????????·?????ü?????ò?????????à?·TVS?ó?????????????÷???????ê?????????·??±??¤??
°??ü/?????????????·?????????????????÷???????????????????ó???????¨??TVS?ó?????????¤????
????????/USB2.0????????????480Mbps????????????????????1G???????ò??????????????LCTVS???ü?¨????????????????????????TVS?????????????????????????·??????(??????3pF)???????????????·?????ó??
SIM?¨/?ì??????ר???????à?????è??????ESD(TVS)/EMI/RFI·??¤?????????????÷??????·????????????÷????????????·?°???
????/???????????????±?÷???·???????????????÷???????????????á???????????????÷????????????????TVS?????÷±??¤???????÷????

???????????????????÷???±????±??????÷???¤×÷?????è?????????????ü???????ù??±?±??¤???·?????÷?°????????ESD???÷?????÷????·???????×????ì????????×????????÷?????????????§·???±??¤?÷????×÷????·????ü???í???????????ü???????÷???????±?×????????

???à°??????§???á?????à????????TVS??????·?×°??????????????SOT23??SC-70?????°???????????ó??????×°???????à??????·?×°????°?????????4.8mm2?????????????????±±??¤?à?????·??×??ü???í?à???ú?·?ü??????±????è±????????????????????ó????EMI/RFI/ESD±??¤???????????÷?????????????????§?????????????ó?ó????????±??????????÷????????±??????¤??±??????????±?è????????±??¤?????????????????????è???????×????

PCB????????

????±??????è±????????÷?à???????·???????????????????á?????ü????ESD???ü???????????ù???¨?????·?è????????????????????TVS??????±??¤ESD?????????±??±??????????í??PCB??????

?×??????±???×?????????ESD???ù??±???·????????????????á?????·?????????ú×??????????????·???????ó?????????÷????????????IC?????????????ì?????????????ú?ú??×?????????????±???????????±???ESD???÷????±????÷?×????·?????×????????????ú×??????ù±????ò????????????·??÷???·??±?????????°ü?¨???????·??TVS??±?±??¤???·?????????·???°????????TVS???¨?·???ù???ò?????ù??TVS?÷?????????????????ü????±?±??¤???·???????ü?????ù???á????×????????????ü???ü???·?????ú?á??

?í???????????????ò?????·??????????
1??±?????±??¤???·???ü×?±??????ü??????????
2????????????°???????????±?????
3??±???±?±??¤???·????????±??¤?????·??????
4???÷?à???????°???????ù?????????·?ù?·????????????????±????±????????±????????ò??????????????
5???????????????·?????????·?±??????±??¤?÷?????????ó?????????·?????ü??·???
6????????????????????????????????/????????????PCB??±?????
7????????????·???????????????
8???????????????÷???????????ó???????????ó?ó???????·°????????????????????????????·??????????·??????ú?????·×??????°?ì??

±????á??

????TVS????????±????è±?????ESD±??¤??????·?±??????§???????????????????ù?????????????í???????????????????????????????ü???í????????PCB?è??????±???????????

×÷???? ????
Email: janejin886@hotmail.com