Simbol Transistor

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Junction Field Effect Transistor Introduction FET Field effect transistor FET are importantdevices such as BJTs Also used as amplifier and logic switches.
What is the difference between JFET and BJT is Current controlled FET is Voltage controlled Types of Field Effect Transistors The Classification .
n Channel JFETp Channel JFETMOSFET IGFET Enhancement DepletionMOSFET MOSFET.
n Channel p Channel n Channel p ChannelEMOSFET EMOSFET DMOSFET DMOSFET Introduction Advantages of FET Temperature stable than BJT Smaller than BJT.
Can be fabricated with fewer processing BJT is bipolar conduction is done by hole andelectron both FET is unipolar uses only one type of current Less noise compare to BJT.
Usually used as an Amplifier and logic switch Disadvantages of FET Easy to damage compare to BJT Junction field effect transistor There are 2 types of JFET.
n channel JFET p channel JFET Three Terminal Drain D Gate G.
Source SDrain DrainSource Sourcen channel JFET p channel JFET N channel JFET.
N channel JFET Major structure is n type material channel between embedded p type material to form 2 p n junction In the normal operation of an n channel device .
the Drain D is positive with respect to theSource S Current flows into the Drain D through the channel and out of the Source S Because the resistance of the channel dependson the gate to source voltage VGS the drain.
current ID is controlled by that voltage N channel JFET P channel JFET P channel JFET Major structure is p type material.
channel between embedded n typematerial to form 2 p n junction Current flow from Source S to Drain Holes injected to Source S through p type channel and flowed to Drain D .
P channel JFET Water analogy for the JFET control JFET Characteristic for VGS 0 V and 0 VDS Vp To start suppose VGS 0 Then when VDS is increased ID increases .
Therefore ID is proportional to VDS for small values For larger value of VDS as VDS increases thedepletion layer become wider causing theresistance of channel increases After the pinch off voltage Vp is reached the ID.
becomes nearly constant called as ID maximum IDSS Drain to Source current with Gate Shorted JFET for VGS 0 V and 0 VDS Vp Pinch off VGS 0 V VDS VP ID versus VDS.
for VGS 0 V and 0 VDS Vp JFET Characteristic Curve JFET for Application of a negative voltage to the gate of a JFET JFET Characteristic Curve .
For negative values of VGS the gate to channel junctionis reverse biased even with VDS 0 Thus the initial channel resistance of channel is The resistance value is under the control of VGS If VGS pinch off voltage VP .
The device is in cutoff VGS VGS off VP The region where ID constant The saturation pinch off The region where ID depends on VDS is called the linear ohmic region p Channel JFET.
p Channel JFET characteristics with IDSS 6mA and VP 6 V Transfer CharacteristicsThe input output transfer characteristic ofthe JFET is not as straight forward as it is.
for the BJT In BJT which is defined as the relationshipbetween IB input current and IC output Transfer Characteristics In JFET the relationship between V GS input.
voltage and ID output current is used todefine the transfer characteristics It is calledas Shockley s Equation VGS ID IDSS 1 VP VGS OFF .
VP The relationship is more complicated and notAs a result FET s are often referred to asquare law devices Transfer Characteristics .
Defined by Shockley s equation I D I DSS 1 GS VP VGS off VGS off Relationship between ID and VGS .
Obtaining transfer characteristic curve axispoint from Shockley When VGS 0 V ID IDSS When VGS VGS off or Vp ID 0 mA Transfer Characteristics.
FET Transfer Characteristic Curve JFET Characteristic Curve Exercise 1Sketch the transfer defined byIDSS 12 mA and VGS off 6VGS ID ID .
VGS VP 1 0 IDSS IDSS 0 3Vp IDSS 2 VGS ID IDSS 1 0 5Vp IDSS 4 VP .
Exercise 1Sketch the transfer defined by IDSS 12 mA and VGS off VGS ID IDSS 1 VP .
VGS 0 3VP IDSS 2 ID VGS 0 5VP IDSS 4 VGS VP 1 IDSS Exercise 2.
Sketch the transfer defined byIDSS 4 mA and VGS off 3 VVGS ID ID VGS VP 1 0 IDSS IDSS .
0 3Vp IDSS 2 VGS ID IDSS 1 0 5Vp IDSS 4 VP Sketch the transfer defined byExercise 2 IDSS 4 mA and VGS off 3V.
VGS ID IDSS 1 VP IDSS 4 VP ID VGS VP 1 .
IDSS VGS 0 3VPVGS 0 5VPBJT is Current-controlled FET is Voltage-controlled Types of Field Effect Transistors (The Classification) JFET MOSFET (IGFET) n-Channel JFET p-Channel JFET n-Channel EMOSFET p-Channel EMOSFET Enhancement MOSFET Depletion MOSFET n-Channel DMOSFET p-Channel DMOSFET FET Temperature stable than BJT Smaller than BJT Can be fabricated with fewer ...

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