electronica 1 mosfet

8/10/2019 Electronica 1 Mosfet

1/49

Thomas L. Floyd

Electronic Devices, 8e

Copyright 2008 by Pearson Education, Inc.

Upper Saddle River, New Jersey 07458

All rights reserved.

Figure 8-1 A representation of the basic structure of the two types of JFET.


2/49

Thomas L. Floyd





Figure 8-2 A biased n-channel JFET.


3/49

Thomas L. Floyd





Figure 8-3 Effects of VGS on channel width, resistance, and drain current (VGG = VGS).


4/49

Thomas L. Floyd





Figure 8-4 JFET schematic symbols.


5/49

Thomas L. Floyd





Figure 8-5 The drain characteristic curve of a JFET for VGS = 0 showing pinch-off voltage.


6/49

Thomas L. Floyd





Figure 8-6 JFET action that produces the characteristic curve for VGS = 0 V.


7/49

Thomas L. Floyd





Figure 8-7 Pinch-off occurs at a lower VDS as VGS is increased to more negative values.


8/49

Thomas L. Floyd





Figure 8-8 VGS controlsID.


9/49

Thomas L. Floyd





Figure 8-9 JFET at cutoff.


10/49

Thomas L. Floyd





Figure 8-10 A biasedp-channel JFET.


11/49

Thomas L. Floyd





Figure 8-11


12/49

Thomas L. Floyd





Figure 8-12 JFET universal transfer characteristic curve (n-channel).


13/49

Thomas L. Floyd





Figure 8-13 Example of the development of an n-channel JFET transfer characteristic curve (blue) from the JFET drain characteristic

curves (green).


14/49

Thomas L. Floyd





Figure 8-14 JFET partial datasheet. 2003 Fairchild Semiconductor Corporation. Used by permission.


15/49

Thomas L. Floyd





Figure 8-15 gm varies depending on the bias point (VGS).


16/49

Thomas L. Floyd





Figure 8-16 Self-biased JFETs (IS ID in all FETs).


17/49

Thomas L. Floyd





Figure 8-17


18/49

Thomas L. Floyd





Figure 8-18


19/49

Thomas L. Floyd





Figure 8-19


20/49

Thomas L. Floyd





Figure 8-20 A self-biased JFET and its transfer characteristic curve.


21/49

Thomas L. Floyd





Figure 8-21 The intersection of the self-bias dc load line and the transfer characteristic curve is the Q-point.


22/49

Thomas L. Floyd





Figure 8-22


23/49

Thomas L. Floyd





Figure 8-23 An n-channel JFET with voltage divider bias (IS ID).


24/49

Thomas L. Floyd





Figure 8-24


25/49

Thomas L. Floyd





Figure 8-25 Generalized dc load line (red) for a JFET with voltage-divider bias.


26/49

Thomas L. Floyd





Figure 8-26


27/49

Thomas L. Floyd





Figure 8-27 Variation in the transfer characteristic of 2N5459 JFETs and the effect on the Q-point.


28/49

Thomas L. Floyd





Figure 8-28 The change inIDbetween the minimum and the maximum Q-points is much less for a JFET with voltage divider bias than

for a self-biased JFET.


29/49

Thomas L. Floyd





Figure 8-29 Current-source bias.


30/49

Thomas L. Floyd





Figure 8-30 The ohmic region is the shaded area. The characteristic curves are straight lines with a slope of ID/VDS for small values ofID.


31/49

Thomas L. Floyd





Figure 8-31 The load line intersects the curves inside the ohmic region.


32/49

Thomas L. Floyd





Figure 8-32


33/49

Thomas L. Floyd





Figure 8-33


34/49

Thomas L. Floyd





Figure 8-34 Representation of the basic E-MOSFET construction and operation (n-channel).


35/49

Thomas L. Floyd





Figure 8-35 E-MOSFET schematic symbols.


36/49

Thomas L. Floyd





Figure 8-36 Representation of the basic structure of D-MOSFETs.

Fi 8 37 O i f h l D MOSFET


37/49

Thomas L. Floyd





Figure 8-37 Operation of n-channel D-MOSFET.

Fi 8 38 D MOSFET h ti b l


38/49

Thomas L. Floyd





Figure 8-38 D-MOSFET schematic symbols.

Figure 8 39 Cross section of conventional E MOSFET structure Channel is shown as white area


39/49

Thomas L. Floyd





Figure 8-39 Cross section of conventional E-MOSFET structure. Channel is shown as white area.

Figure 5-34 drain characteristic of n channel enhancement type MOSFET


40/49

Thomas L. Floyd





Figure 5-34 drain characteristic of n-channel enhancement type MOSFET.

Figure 5-35 Sketching the transfer characteristics for an n-channel enhancement type MOSFET from the drain characteristics


41/49

Thomas L. Floyd





Figure 5 35 Sketching the transfer characteristics for an n channel enhancement type MOSFET from the drain characteristics

.

Figure 5-37 p-Channel enhancement-type MOSFET


42/49

Thomas L. Floyd





Figure 5 37 p Channel enhancement type MOSFET

.

Figure 8-44 E-MOSFET general transfer characteristic curves.


43/49

Thomas L. Floyd





g g

Figure 8-45 D-MOSFET general transfer characteristic curves.


44/49

Thomas L. Floyd





Figure 8-46 Common E-MOSFET biasing arrangements.


45/49

Thomas L. Floyd






46/49

Thomas L. Floyd






47/49

Thomas L. Floyd






48/49

Thomas L. Floyd






49/49

Thomas L. Floyd





electronica 1 mosfet

Documents