Fet As Vvr



Electronic Devices and Circuits S. Salivahanan download Z-Library. Download books for free. We consider the use of a n-channel FET as a voltage controlled resistor where the resistance between the drain and source is controlled by the gate-source voltage. There are two distinct regions. In the Ohmic region1, the drain-to-source current, I DS, depends on the gate-to-source voltage, V GS, as well as the drain-to-source voltage V DS.

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Chapter 82003.11.6- (FET), .2 FET(Field Effect Transistor) :-- FET(MOSFET: Metal-Oxide-Semiconductor FET) :,-FET(JFET : Junction FET)) / ) 10 85 . 8 )( 9 . 3 ( - ( ::14cm Ftoxox - FET(MOSFET) , .2 MOS - FET(MOSFET)P MOSN MOS- FET(MOSFET)N- MOSFET 2 n- .MOSFET - .- FET(MOSFET) ( ). . . . . . .- FET(MOSFET)+VTH : (n- MOSFET)VGS < VTH : iD = 0:- pn VGS > VTH : iD( - ) , . MOSFET- - FET(MOSFET) MOSFET- - VGS > VTH , VDS : .VGS > VTH , VDS: . ,. .VDS iD .- FET(MOSFET)VDS = VDS(sat) : VDS > VDS(sat) : ( ) 0 . . MOSFET- TH GS DSTH DS GSV v sat vV sat v v ) () (- FET(MOSFET) - , vGS>VTH - - kn n- (conduction parameter) [ ]2) ( 2DS DS TH GS n Dv v V v k i 2) (TH GS n DV v k i DS DS oi v r /2) ( 2TH GSD ox nnV viLC Wk ' :L:::W) /t ( Cnox ox ox- FET(MOSFET) : . :( ). : . : pn . : . .[n- MOSFET][ ] [ ]- FET(MOSFET)n MOSFET 0 , n- . 0 . 0 . . MOSFET , MOSFET MOSFET [n- MOSFET][ ] [ ]- FET(MOSFET)p MOSFETp- p- .n- . - . n- . p- MOSFET [ ]2) ( 2DS SD TH SG p Dv v V v k i + 2) (TH SG p DV v k i + 2) ( 2TH SGDox ppV viLC Wk+ [p- MOSFET][p- MOSFET]- FET(MOSFET)(Complementary) MOSFET : CMOS - :, , iD vDS . , .[ ] / 1 , 0 ) 1 ( 0) - : () 1 ( ) (2 + + A A DS DS DDS TH GS n DV V v v iv V v k i ( ) [ ][ ]DQADQDQ oTh GSQ n oIVII rV V k r 1112 - - .vSB0 (PN ) vTho vSB = 0 .r ( 0.5V1/2)F , 0.35V . .[ ]F SB F Tho Thv r V V 2 2 + + - (Subthreshold Conduct) : vGS VTh , 0 . . .2) (TH GS n DV v k i ) (TH GS n DV v k i - PN . . 10V . k . VGS ., . .. VGS .JFET(Junction FET) 3 .,.p- JFET, n- FETJFET(Junction FET) = 0A, VP : IDSS: VGS=0V VDS>|VP| JFET .JFET(Junction FET) JFET .Shockley 21

VvrApplication

Fet As Vvr And Its Application

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Fet As Vvr Pdf

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Fet As Vvr

.| DSSDP GSIIV V 1) 25 . 0 (2 /3 . 02 / DSS DP GSP GSDSS DI IV VV VI I[n ][p ]JFET . 0) ( G GC D S D RR A II I R I VS S SR GS R GSV V V V 0) 2 / (2) (DSS DS DSSS D GSI IR IR I V ) (0 D S D DD DSD D S D DD R R DD DSDD R DS RR R I V VR I R I V V V V VV V V VKirchhoffS SS S+ + + S D S GR I V V V , 0 *