积分电路.ewb

EWB仿真电路实例集锦

Electronics Workbench Circuit File
Version: 5
Charset: ANSI
Description: 
"" 

EncryptionType: 1
UsingVectorGraphics: 0
/DKDFAAAPBNHLFEBMDKEHACAKHCFA
FDEKEJDHHLBHBKBKDMFGAGCMAHDDEFFLBLDOAADAHJBCCDAMBBGAAABCFIENAOGD
BAFBAAAGHIACBHAJBPEPAHAKFHDEGIAACDADBFGCHFFGCMAGDAGHBLACGNELAOFF
DKDFAAFGDDFEFEDKHJEHAFAEEDDEGIAAGKDJCNGCGFAECDBLDLHNCFGNDGBPFHBI
DNBIFLHOBKFGAHAEDMEGAHCIAHDDEFFLBLDOAADGHFADCBBLDAFHGDGKEGDFGKFN
FBGICKHJDHFEBIAJDMEGABEHCNGMEFEFHMFCGOEIBBFGDJGDFEDEAFACFPFACKCK
ABBIBGEEDMBDEFEIGLBDFCBHCNENAIEBGDFCHAEIBBFGHHFIHJHNEJAKEOHBBDFC
BAAKBBFPHCEHFEFIGIAJANFECNAOEFBADBADAAHCCOFLGCFJGLDEFIEHALAOEMEF
FPHFCKHJDHANHOGFHJFBANAGGDFLBHEFHHFGFCBCBGHLDPGDFEGJGDGKBLAPEHBA
BAAIAAEFDHEGEEFJHJBCEIFECNAOFEBKHIBDEPCEHCDPEIGEHJCCFIEHFCBPACEE
AABIEJFEGEBDBAAHBHFFAHANFODEGIAACBBDBAHECLEDHKFNGJCFEJFGBLAOEHBB
BAFNENBFFJHMHJEICCCIGFEFGBFLAHEBFNDJCNGCGHHMEPEJCKGAAHAIHNDFGKAA
BAFBAABBGHAPCAGCFEACFNFECABOAMAAHEEJEJBBBGHLGCELDFHFAABFHKBNEHHC
BAFEEFBAHIDLHOGFCECIGFEFDNAGFDBBCAAEBGHDDMBPGCBLDGHIAGCEDBDCEHBA
ABBFAABNDHBDAOABAKCIGFEFCPFCAEEJGDHCACGCEOFGCHAEDIFKGDGKBLEEGNCN
BAAIBIECCGEHEDFOGIACABEFHPFBAJEPFCDJCNGCCMFGCLEJDMGEBADDDBDCEHBF
EFEKFEAHHJDPHOGFHJFJGCGICNENBBEOHEFOEFCOFJHMEPBEFDBJBEGNDGECGNCN
ADACEJFEGEBJCEGCFEACFMEFGEBOAIFFFPEHFCCDEMHMEPEJCCBOGEEHEPFBACEN
EEEKEBCEBNHLFEBDFDCPEIBFGAFBCGCKBMEOCKEPDMEPHDFBHJCEFBFFAKBPFHAA
AHAABIFECHEEENEIGJACFLFPGEBOALEPHIEHEJDBHDCGEIGEHJCFEJAOBLFCBCGO
EDEMEJBKECBKBBAMDGGPGCGICNAOEFBADBADBBGCCPEMDAEJDMGBAFAGGNDFGKAA
EEGLCKHJDHFEFGEIALACANAIGMHAAJEFHFFMGNEIBBFGHCEJGJDEFIEHAIAFAOAA
FNFHGDHOBKALHOGFHJAAFJDHCPBODHAAFFHKEGCHEOHMEPEJGJDEAAEHEIEKBDEB
BAFGEPBNGDBPAHAHAJCIGFEFDEANEFEJDBFOFFAMGIAECDDJFDBJEJBMDBDCEHFA
FPHFCKHJDHEGFEFJGDFAEIAAHIFCAEHGBLDOAAHECJEOGCFLGICNEJFHBLAMFNEJ
FFGKCKHJDHEGFEABHJFBBNBBGMEKDGCKBMBDBAGCCNEMCLEJCKGAAAAJGOFDACEE
FNDCCNFEDFEDDKCGBGGBEKEFEMBOBHFEGBEDHPCPBGHLGCELGMDGEJDFBLHLCOEG
FNDCCNFECOECEMEIDAACAOADGCGBBMHPHMDJCNGCCFEGHLEJDADEAPABFEGABPHP
GPFBHPBJBNHLFEFIHJFAEIABGDFBAGHPHIGMENEIBBFGHKEJDADEBKAAFKFDABHP
BAEIENBLFEHMHJBFFDCPEIFFCNFHEFEBGDEHFICHEDBLEIGEHJCEEJBFBLFGBFEO
ADACEJFEHJBJBNBMDAFBAHDFAHDDEFBJDBFKAACPGJDIDGBLDIEEGDGKBLEEGNCN
FMFNEEBLFKHMHJEIGJACFJFPHPBOAAFFHNFCHGEIBBFGHCFNGBDEFNFHACBPFHAA
HEHBEGBBEFHMHJEIGJACABEFHOELBBEBGFGACKEPDMEGGCFIGDHNEJBEEPFGAJHF
DNEFCKHJDHFEEBEKHJGDEIFHFCFKAJEFHIFFFIEIBBFGGAFMBHFKCGCEBJBPDFAA
DKDFAAEGDHBPFEAFCMGMBMBHGMGOGPCNDBEICKEPDMACCMAMDEGBBLBDEIFBCOCK
BAEDCKHJDHAGBJAHBKCIGFBIAHDDEFBHCEALAAHBCKEBGCFJHJCHFDAOBLEMAIHA
BAAIAAEHCNBPFEAGDGELBMAMHOFBDFCKBMBDBIHBDMBPGCAECMFKBNBFFKGPGNCN
GFFEEFBAHIDLHOGFHJBAFLEFDMAEBHAAHEEGEMCDEKHMEPEJGOCCFAEHAPAKFGBB
EEGLCKHJDHFEFGEIALACANAIGMHAAJEFHFFMGNEIBBFGHCEJGICOAAEHEIELAOEO
FNFHGDHOBKALHOGFHJAAFJDGCPBODHAAFFHKEGCHEOHMEPEJGLDEAAEHEIEKBDEB
FJBIEOBLHOACBNBLDGHCGCGICNAHEFEJDBFOFFAMGIAECDDJFDBJEJBMDBDCEHFA
FPHFCKHJDHEGFEFJGDFAEIAAHIFCAEHGBLDOAAHCCPEBGCFNGKCEFIEHALBPFEBK
FFGKCKHJDHEGFEABHJFBBNBBGMEKDGCKBMBDBAGCCNEMCLEJCKGAAAAJGOFDACEE
DNBIACEEDFFGDFEIGLHNAMAJGIFHADFIBLDOAAGACIDIAMCGBKDGEJDFBLHLCOEG
FPGICKHJDHEPEHEIDAACAFBAEDEKBHEBEBDJCNGCGHHMEPEJCJHJAGCEDBDCBKCK
AKEKAABBGCBKBFDOFDCPEIFDDEAGEFBCCDABBBGCCMFGHBFDDADEAHAIFCELAOFD
BAELFFAAHGACCHGCFEACFIEFDMAEAMAAGCEHEJCMEJBKCHANDGFJGDGKBLAPEHBB
HPHLACFEFGFGAGBMCJFCDHAIAHDDEFACCHBBAABADMDCALAPDMEGGDGKBLAPEHEJ
BAFOEGBLEIAPCLAFFDCPEIFMDMAMFEAAHIBDEGCEHDCJDKDGDEBOGEEHBJAMCJGO
ECBIEEBKHIBFCLABAGEPGCGICNAOEFEJDBEAEHCDHABABNAEFDBJEJFOADAHEHEJ
DNBIBAFEHOFGBFBKCNFKANDKGADEGIAACBBDFCGCHFAECMDGDAELAEGNDGBPFHAA
EDFHHAHOBKFGENEIDAACAFBAEDEKBHEBEBDJCNGCGHHMEPEJCJHJAGCEDBDCBKCK
ABACFCFEHCADBIAJAPCIGFEFDNAGFNAACFACBCHDDMEGGCFKGDHNEJAJFEFGBDEJ
FJBIFDABGDBHAADLFDCPEIFFCNAPFPEJDBEAFECLHCCDCOAMDNHLCEGNDGBPFHAA
BAAKHPBAHLBDBNAOCBCIGFEFCPANCLGOFOHAACGCEOFGAGCADPHBDLGNDGBPFHAA
BAFBAABJGCDIAABKDIHCGCGICNEFGPCNDBEDENCNFPHMEPBEFDBJEJEFANBNEHGB
FBGOCKHJDHEBEDFBHJBFFNFFDMBOFFAACCAJEJGCHCBJCLBNDAGHAGDHDBDCEHBB
FJBIFDAAHOBICBAEDMEGAHCIAHDDEFBADBADAAHECMFNCHFIHJCHFDBFBLFKBCEM
EEFJFECHBNHLFEEKHLACDKEFGIFDAEGOHNFGEECNFBHMEPEJGJDEFJEHAKBPFEBK
BAEIENBLFEHMHJBFFDCPEIEHDOGMEHAAEDBDGEALHKBDBAGDFEDEFJEHFCBPBEFF
ADACEJFEHJBJBNBMDAFBAHDFAHDDEFBBDBFKAACPGJDIDGBLDIEEGDGKBLEEGNCN
DNBIBAFECHFGEEFJHJBBFCBHCNFLBAEMHAGFCKEPDMEBHHFOHJCMFLFHAKBPFGAA
FNFJGOBIHCBCBLCFFDCPEIFFCNAOEFBBDBAABKCLDMAFDGAADHEBAFACFPFACKCK
GCBKAACGDHDCDNAODMHAGCGICNAOEFEJDBEAFFDGHNACBBGDFEDEELEFBLGNEHEF
DNBIBIFEHOFGBJBNBHFGBKAEFNDEGIAAGKDJCNGCGMBLCNCKFDBJBEGNDGBPEFBC
BAFNFFBIHGCAHOGFHJBHFMFCCNAGFDBHDBADAAHBCGBPGCAHDGHNBNAOEIFADHCK
EFEMEBAAEEHMHJEIGJACFJFPGEBOBGFEHIFNHFCOHJBCCNCEFDBJEJFHBLAOFNFC
DKDFAAAEHKBJDHGCFEFPGCGICNBMFFACDBGBAAAGFFBACHDLFDBJEJFHBLFGEHFD
AABIBDEOHOFGBKAHDAFGABBGGCGOGPCNDBALAACLDMBLDHCHCNGGAIDHDBDCEHFL
GFFEEFBAHIDLHOGFHJBCEIFEDHEMEFEFGEFPEBBEBGHLGCFJGBCCEJFPAKAPFGAA
BAHMGJBCHCCEHOGFHJBCEIAMCNENBAFEHAEHHDEIBBFGHCEJGICOAAEHEIELAOEO
BAFBAABJGCDIAABKDIHCGCGICNEFGPCNDBEDENCNFPHMEPBEFDBJEJEFALBNEHHC
FBGOCKHJDHEGEMFAHJBGFNFEDMBOFFAACCAJEJGCHCBJCLBNDAGHAGDHDBDCEHBJ
GDDCCNFECHFGEFFCDAACBLBBGEFADAEMHEFHEPAPBGHLGCFJHJCFFDBFBLFKBCEM
FGEACKHJDHFEEGCGBHGNCLEHCNGMEFGEFIFFEFBABGHLGCFJHJHNEJBEEOELAGFE
ECFJHAHOBKFGAPGCFEACBIAIGCHNGPCNGMDJCNGCDOEAGAEJBIDEFLDIFPFDACEJ
BAAPBDEFCGFGEEEIGKBIABEFGDFBAMFEHIEAEPBCBGHLGCFAGKDEAAEHFGEKCJFE
FJBIFDAAHOBICBAEDMEGAHCIAHDDEFBADBACBKDADMBDDHAFDIECGDGKBLALFOBJ
BABKBEFGDHCEFECMBAEEANDHAHDDEFBADBFKAADBGJACCDBNAKBOGEEHALBPFGBK
DKDFAAEDCEEHEFEIDAACAOADGCGBBNHPHMDJCNGCCOFGCLEJCLGABJBHGEFCGNCN
GPFFCKHJDHECFEABHJFBAPAEGBFIDKENBLDOAAHCCFEPGCAAHJHCAPAIGEEGDIEN
EEEAEFCLHKHMHJEIGJACBKEFGEEMALHPHIGMENEIBBFGHCEJCLDEANAJFEFMDIEJ
FJBIENABFJACAGAJAJCIGFEFHGDEGIAAGBFOEPABBGHLDPGDFEDEFJEHFCBPAGFC
GGDCCNFECHEFENEIGNBDFIFECNAOEFBDCLFKAACMHDBPDGAACKHLDJGNDGBPFOAA
DKDFAAEEDHEHEOABHJFBBMAMGDGLAJEFHFFMGNEIBBFGHCEJGICOBLEHFOEKALEB
EIDCCNFEDFEHDKCGBGGBEKEFFPBOCBGJHHFGHCEIBBFGHCEJDADEBKBCEPFOBDHD
FBGICKHJDHANHOGFHJFCAFAKEODEGIFNBLDOAAGACOFEGCCIHJCGDGADFHFKAOEG
ACAKBAEFDHEGFEFLGDELEIALGCFHBBEJGCFMHAEIBBFGHLFKHJHNEJAKEOHBBDFC
BAELFEBNHJCDBIANDNENCFGPAABOFFAACAAJFCGCHJADCOAIAPBOGEEHANAPFOAA
BCAKACFEEFFGDACBDPEHDKGPAABOFFAAHIBDFDDHGIBHDGDKFDBJEJFHBLAOFNEJ
BAFBAABCHBBJCLBAAGEPGCGICNBMFFGOFPHMGDGADMDHGCBLCNGEBJDIFGDFGKAA
FJBIFDBDHGBKBCDHDECIGFEFDEAHFNAAHIBDEGCEHDCJDLDGDEBOGEEHACAOFHBB
BAAIAAAGDHBPAGAGAGELDHAIAHDDEFBADBEBAACGHCBJCBDGDAELAEGNDGBPFHAA
FBGICKHJDHANHOGFHJFCAFAKEODEGIFNBLDOAAHCDMBPGCAICLGABBACGEFCGNCN
BAAMBBEECGFGEEEIGKBIABEFGDFBAMFEHIEAEPBCBGHLGCFAHJHNEJAKEOHBBDFC
FJBIFDAAHOBICBAEDMEGAHCIAHDDEFBADBACBKDADMBDDHAFDIECGDGKBLAPFOBI
HOHHGDFGDHCEFECMBAEEANDHAHDDEFBADBFKAADBGJACCDBNAKBOGEEHALBPFGBK
DNBIFABJHIDFHOGFCECIGFEFCPAMEHAAFABDBCBNHIBKCHAADPGMGDGKBLBNFHGO
BAALBKBNDHBIBLABCNELBLAKFNDEGIAACCBDEJGCHBADAMBNCLHFDJGNDGBPBMCK
FMFNEEBLFKHMHJEIGIACFJFPHPBOAAFFHNFCHGEIBBFGHFFIGADEFAFPALAOEHBA
GDDCCNFEDFFEFEDKHJEHAFAEEDFCAAEEHOHOCKEPDMEEGCFIGDHNEJBEEPFGAJHF
FPHLCKHJGKHMHJEIHLBDCLEHCNGMEFGEFIFFEFBABGHLGCFJHJHNEJBEEOELAGFE
FOFHEJAAHOAFBLDIFDCPEIFMDOBOAMAAHMEGGODGGOBHBCGDFEDEBCGNDGBPBHEN
DKDFAAEEDHEHEOBKHJEHBNAJGMGIGPCNDBADBFHKDMECHGFJGIDEFJEHAIAFAOAA
DKDFAAEEDHBPFEBLCMFGAJBBFODEGIAACBBDBBHIHFFGDBBNDAHKDMALFOFLAIGN
FPGHFICLHKHMHJEIGNACABEFHPEKBFFAEOFOCKEPDMFEHDELHJEGEJCDHCFJACHC
FMFOHPBJBNHLFEFIGMBKEIAMCNFIADEPEOEKHPCPBGHLGCFJGNCEFIEHFCBPABEG
FJEKEOCLHOCJBJGCFEACFIEFHPBOABEOHOFAHPCLEDBLEIGEHJCAEJAOBLEMAAEB
ELDCCNFEGHBLBLCLFDCPBFGPAABOFFAAHIBDEBDAGIAOCHDGDEBOGEEHALBPBFAA
AABIBDEOHOFGBKAHDAFGABBGGCGOGPCNDBAGBBGCHFFGCPBMBHGABLAGGLDFGKAA
HNDCCNFECHFGEFFCDAACBLBBGEFADAEMHEFHEPAPBGHLGCFOGMCMEJFBANAPFGAA
BAAIAABNDHAFABBMDIFGDLGPAABOEHEMHAFGEECLDOFGBAEJDMHJAICJFHFKADEP
DKDFAAAHHCAEBNDPFDCPBFGPAAEDGPCNDBBBBBBAFNFEGCDLHJFACAABFOGNGNCN
BAAIAAEDCGFGEFEIGIACFMFPGEBOBGEPGBDJCNGCGHHMEPEJDMGGAABADBDCEHFL
EHDCCNFECHFGBNEICLFHAHAJGCFNGPCNDBAHBDGCCNFGHAFDDADEBKAAFOEMGNCN
EHDCCNAJBNHLFEEKGLAAEICECNEODKEFHFFMEOEIBBFGHCEJDADEANAOGEFKBFEJ
EDFPEFAHBNHLFEFIHJBDEIFECNANEFBECLFKAADBHDAGEIGEHJGPGDGKBLFKBFEJ
FJEPCKHJDHEGFEABHJFABNAKGBFBAGCKBMBDBCHDDMEHGCFPGNDEFLEHAPAFAOAA
FJEPCKHJGKHMHJEIHLBHEKEFEMBOBFHPHEFHEPCMBGHLGCFJHJHNEJADFCGAACFC
BAELEHBBGEHMHJEIGJACFIEFDOBOFGAACFAJEJGCGPBJDCGDFEDEBCGNDGBPACFC
AABIEJFEGFADBLAEDGEBGCGICNAMFDAACDBDBAHCCIFGHDEJGPCMEJFPBLAJFNEJ
DKDFAAFGCCFEFECJHJFCDHAAGJFBALCKBMBDBAGCHFFGCGAAAGHBBLAOEMDFGKAA
DNBIBAFECGEHFEFJHJBGEIFBDHFHEFFDHOEDCKEPDMANEIGEHJHBBLAOEMDFGKFN
ECENEPBIHIBFHOGFHJBGFJEFDFBOFNAACABDBJHHDMEOGCFPGDHNEJBEFMFKBECK
AABKAADFDHAGCLANDNENAGGPAABOFFAAHIBDEECLEDBDDAAACOBOGEEHALBPAOAA
BAALAAEGDHECFEFMGDELEIBGGCEOGPCNDBEICKEPDMBDDAAACOBOGEBKDBDCEHAC
BAANBBFECGFGEGEIGLACFPFMCNAPEFBDCABDBIGCCEEMCLEJCKHDAMBEDBDCEHBA
FEFHEOHOBKFGEEEIDAACAMAMFCFLBHEJGGDJCNGCCMFGCLEJCLGBAGALFEFMGNCN
AKFBAAAHHIAGHOGFHJFJGCGICNFLBHEJGGDJCNDPBGHLGCELGMDGEJCGBLEPDIEF
DNBIBGEMDHEOFEFMGIACFJEFDJAEAMAAGCFEEFDBBGHLGCFIHJCMEJFGBLAKEHBE
FEFHEOHOBKFGEEEIDAACAMAMFCFLBHEJGGDJCNGCCIEHGCAAHJGGBMAIFHFAAECK
AKFBAAAHHIAGHOGFHJFJGCGICNFLBHEJGGDJCNDPBGHLGCELGPDGEJCGBLEPDIEF
FMFHEDHOBKFGECFJHJBAEIFHDHFHEFFDHGFGFDEIBBFGHCEJGJCFEJFGBLAJEHBE
HBBIFACLHCBCBLAGFDCPEIFFCNFHEFEEHIGMEFDAHFABEIGEHJCEEJAOBLENBCEP
ACBIBGFECDEMBNEICKENBIGPAABOBOCKBMBDEFDAHFABEIGECEBOGEEHBJAPEFAA
BAAMBBFECDFGECFBHJBAEIFGDEAMEFBBDBAFBKCLDMAFCFAMCKBOGEEHAIBPFHAA
FEFHEOHOBKFGEEEIDAACAMAMFCFLBHEJGGDJCNGCCMFGCLEJCLGBAGALFEFMGNCN
AKFBAAAHHIAGHOGFHJFJGCGICNFLBHEJGGDJCNDPBGHLGCELGJDGEJCGBLEPDIEF
FMFHEDHOBKFGEAFJHJBKEIFHDHFHEFFDHGFGFDEIBBFGHCEJGLCFEJFEBLAJEHBE
HBBIFACLHCBCBLAGFDCPEIFFCNFHEFEEHIGMEFDAHFABEIGEHJCEEJAOBLENBCEP
ACBIBIFECDEMBNEICKENBIGPAABOBOCKBMBDEFDAHFABEIGECEBOGEEHBJAPEFAA
BAAMBBFECDFGEFFAHJBKEIFCDNAPEFBBDBALBKCLDMAFCFAMCKBOGEEHAKBPFHAA
AABIEJFEHDBPCLANCLELBPGPAABOFBBBDBFKAADAGJBJCOAGDKBOGEEHAPAOEHBC
DKDFAAAPBNHLFEANCLELBPGPAAEDGPCNDBBBBGGADMDHGCBJAGHBANAIFFDFGKAA
BAAPBDFECGFGEGFCDAACBLACGIENGPCNDBADAAHHDMEHGCFAHJCAFDAOBLEMAIFA
FEFHEOHOBKFGEGEIDAACAMAMFCFLBHEJGGDJCNGCCMFGCLEJCLGBAGALFEFMGNCN
AKFBAAAHHIAGHOGFHJFJGCGICNFLBHEJGGDJCNDPBGHLGCELGNDGEJCGBLEPDIEF
AIAKAAEFDHEGECEIGLACFMFPGEBOBGEHHEEACKEPDMEGGCFJGLDEFIEHALAOEHBE
FPFGCKHJDHECFEABHJEGABDKGIEMAMFHBLDOAAHCDMBPGCBLCMHLAFAIFIDFGKAA
FJBIFDBLGHHMHJEICCCIGFEFGIEMAMFHBLDOFNEIBBFGGAFIHLDECIEHELGAACEE
FPFLCKHJDHEFEBEIGIACFKFPGEBOBGEHHEEACKEPDMEGGCFBHJCGEJFEAKBPFDBK
EAGHEFBAHIBIHOGFHJBCEIAMCNFKAMHPHEEBEJDFBGHLGCFNGIDEAAEHEJEKAIEM
ABBIBEEOHOFGAHAHCJCIGFEFHGDEGIAAHEEBEJDFBGHLDPGDFEDEELFBBJBPCGAA
FDDCCNFECOEFFEFJHJBEFMEFDPBOFBBKHIBDFDCFHJAFEIGEHJCEEJFOBLAOEHBF
EAGHEFBAHIBIHOGFHJBCEIAMCNFKAMHPHEEBEJDFBGHLGCFJHJHNEJBFEOFAALEP
ABBIBEEOHOFGAHAHCJCIGFEFHGDEGIAAHEEBEJDFBGHLDPGDFEDEELFFBJBPCGAA
EFFHEMBLHEHMHJEIGBBEEIFECNAMFPEJDBEAEHCHGPHMEPEJGJDEFBFGBLANEHBF
BCBIGBFEGHCJBBAMDGEMGCGICNAOEFEJDBFHEJBNHJAECLBOFDBJEJFHBLFGEHFC
BAAJAAEDCGFGEAFCDAACBLAKHNDEGIAAGKDJCNGCHJAECLBOFDBJBEGNDGBPEFBC
BAFBAAAGGCBJBIAHDKCIGFEFDOANEFBCDBABBKCLDMAFCFAMCKBOGEEHAIBPFCBB
DNBIACEGDFFGDFEICJHNANABGCFAGPCNDBADAACLDMBCCLDGDMGGAABADBDCEHBA
ABBIBAEGDHEEFEFPGIACFMFPGEBOBGEPGBDJCNGCGHHMEPEJDMGGAABADBDCBKCK
FPFEEPBHBNHLFEFNGIACFJEFDNBOFNAACBAAAAHDDMEAHIAAHJGHAOACEIDFGKAA
BAHJAAAEEIBDBAAHDHCIGFEFDNBOAMAAHFFKHPCHGOBPDFGDFEDEFJEHFCBPBFFF