What is a unipolar transistor?
field effect transistor
A unipolar transistor is a field effect transistor (FET) that uses only one type of charge for conduction from drain to source i.e. either electrons (n-channel FET) or holes (P-channel FET). FETs are also referred to as unipolar transistors.
What is drain curve?
1. Output or Drain Characteristic: The curve drawn between drain current Ip and drain-source voltage VDS with gate-to source voltage VGS as the parameter is called the drain or output characteristic.
What are the characteristics of FET?
A FET is a three terminal device, having the characteristics of high input impedance and less noise, the Gate to Source junction of the FET is always reverse biased. In amplifier application, the FET is always used in the region beyond the pinch-off.
What is the difference between unipolar and bipolar transistors?
A bipolar junction transistor (BJT) is a type of transistor that uses both electrons and electron holes as charge carriers. In contrast, a unipolar transistor, such as a field-effect transistor, uses only one kind of charge carrier. Hundreds of bipolar junction transistors can be made in one circuit at very low cost.
Why is transistor unipolar?
Theoretically, the field effect transistor can be controlled without power consumption. Only one type of load carriers takes part in the operation of the component, hence the unipolar name, while the control of output current is done with the use of electric field (field effect transistors).
What is output characteristic curve?
Output Characteristics: The curve is got by plotting the output current against output voltage keeping the input current constant. Current Transfer Characteristics: This characteristic curve describes the variation of output current in accordance with the input current, keeping the output voltage constant.
What is drain characteristics and transfer characteristics?
The transfer characteristics can be determined by keeping the drain source voltage VDS constant, drain current ID is observed by changing the gate source voltage. So it is observed that when the gate source voltage VGS is increased in the negative region the drain current ID decreases. Electronic devices Transistors.
What is JFET and its characteristics?
A JFET is a semiconductor with 3 terminals, available either in N-channel or P-channel types. It is unipolar but has similar characteristics as of its Bipolar cousins. Instead of PN junctions, a JFET uses an N-type or P-type semiconductor material between the collector and emitter (Source & Drain).
Why BJT is called unipolar?
BJT is called bipolar because the current in a BJT flows due to both electron and hole carriers, whereas the current in a Field Effect Transistor (FET) flows due to either electron carriers for N-type FET or hole carriers for P-type FET, hence they’re called unipolar transistors.
What are the characteristic curves of a transistor?
Figure 1 Simple circuit for a transistor operation. The characteristic curves of a transistor provide the relationship between collector-emitter voltage and collector current for different values of the base current. Because there are two parameters that affect IC, a set of individual curves shown together denote various operating conditions.
What happens when IB = 0 in a transistor?
When IB = 0, the transistor is in the cutoff region although there is a very small collector leakage current as indicated. Cutoff is the nonconducting state of a transistor. The amount of collector leakage current for IB = 0 is exaggerated on the graph for illustration.
What is the a family of collector characteristic curves?
A family of collector characteristic curves is produced when IC versus VCE is plotted for several values of IB, as illustrated in Figure (c). When IB = 0, the transistor is in the cutoff region although there is a very small collector leakage current as indicated. Cutoff is the nonconducting state of a transistor.
What is the operating point of a transistor?
The operating point of a transistor is a point on these curves, corresponding to a given IB and a given value for VCE. A transistor, nevertheless, cannot work at all the possible points that can be found on the characteristic curves.