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What else can I help you with?
What is input impedance of fet amplifier?
Zin=Vds/Id [Vds=drain to source voltage ; Id = drain current]
Why the name is FET?
FET stands for Field Effect Transistor. The name FET comes because the gate current of a field effect transistor is zero and current present in the source conductor is due to an electric field produced by the substrate material placed between the gate and the source.
Why is it thatFET is called a voltage operated device?
since in an FET the value of the current depends upon the value of the voltage applied at the gate and drain...so it is known as voltage controlled device.. for example..in a mosfet..the current from drain to source depends upon the width of the depletion layer..which in turn depends upon the voltage applied on the gate.. so that is the reason
What are the classifications of FET?
mosfet, JFET ,these are again divded into many typesdepending upon their material they are made of
Can you use a fet as a capictor?
No. Not for any practical capacitor value. There is an inherent capacitance between the gate and the drain/source channel, but it's only a few picofarads.
What is drain resistance?
drain resistane is basically the resistance offered by the drain terminal of the fet device.its the ratio of change in drain to source voltage to the change in drain current at a constant gate to source voltage.
What is input impedance of fet amplifier?
Zin=Vds/Id [Vds=drain to source voltage ; Id = drain current]
How fet is used as vvr?
FET AS A VOLTAGE -VARIABLE RESISTOR (VVR):FET is operated in the constant current portion of its output characteristics for the linear applications .In the region before pinch off , where Vds is small the drain to source resistance rd can be controlled by the bias voltage Vgs.The FET is useful as a voltage variable resistor (VVR) or Voltage Dependent resistor.In JFET the drain source conductance gd = Id/Vds for small values of Vds which may be expressed as gd = gdo [ 1-( VgsVp)1/2 ] where gdo is the value of drain conductance when the bias voltage Vgs is zero.The variation of the rd with vgs can be closely approximated by rd = ro / 1- KVgs ro - drain resistance at zero gate bias and K constant dependent upon FET type.Small signal FET drain resistance rd varies with applied gate voltage Vgs and FET act like a VARIABLE PASSIVE RESISTOR.Advantagesof JFETVery high input impedance order of 100 ohmOperation of JFET depends on the bulk material current carriers that do not cross junctionsNegative temperature coefficientsVery high power gainSmaller size longer life and high efficiencyAc drain resistance rd it is the ratio of change in drain - source voltage to the change in drain current at constant gate source voltageTransconductance it is the ratio of change in drain current to the change in gate source voltageat constant drain source voltageAmplification factor it is the ratio of change in drain source voltage to the change in gate source voltage at constant drain current.
Why the name is FET?
FET stands for Field Effect Transistor. The name FET comes because the gate current of a field effect transistor is zero and current present in the source conductor is due to an electric field produced by the substrate material placed between the gate and the source.
Why is it thatFET is called a voltage operated device?
since in an FET the value of the current depends upon the value of the voltage applied at the gate and drain...so it is known as voltage controlled device.. for example..in a mosfet..the current from drain to source depends upon the width of the depletion layer..which in turn depends upon the voltage applied on the gate.. so that is the reason
What is the use of gate in fet?
This gate permits electrons to flow through or blocks their passage by creating or eliminating a channel between the source and drain.
How do I identify if a field effect transistor is defective in a circuit?
Is you'll need to short circuit between the drain and the source to identify FET test
Is fet having negative resistance?
JFET BFW20 shows negetive resistance when gate is grounded (VGS = 0) and vary Drain to source voltage and measure Drain current. As the voltage is increased, the drain current decreases. Prof.S.Lakshminarayana.
What are the classifications of FET?
mosfet, JFET ,these are again divded into many typesdepending upon their material they are made of
Can you use a fet as a capictor?
No. Not for any practical capacitor value. There is an inherent capacitance between the gate and the drain/source channel, but it's only a few picofarads.
What is CMOS FET transistor?
CMOS stands for 'Complementary Metal Oxide Silicon' and is the construction method of the device. FET stands for 'Field Effect Transistor'. Although it is a transistor and is used in a similar fashion, it is totally different in the way it is controlled and biased. The pin outs are named differently. A bipolar transistor has a Base Emitter and Collector. A FET has a Drain Source and Grid. Current is controlled between the 'Source' and 'Drain' by altering the voltage on the grid. It works in a similar way to the old vacuum tube valves and is why the control is called a grid. It forms a 'pinch off' effect, in the path between the source and drain, instead of the depletion layer in a normal transistor.
As the drain voltage is increased for a junction FET in the pinch off region then the drain current?
Remains constant
