ADVANTAGES AND DISADVANTAGES OF JFET
- The operation of JFET depends only on the flow of majority carriers. Therefore it is called as UNIPOLAR device. On the otherhand in BJT, both majority and minority carriers takepart in conduction. So it is called BJT.
- It is quite easy to fabricate rather than BJTs. JFET is small in size and they offer long operating periods with higher efficiency.
- JFETs occupy less space in circuits due to its smaller size.
- The inputs of JFET is always reverse biased (gate to source) so they provide HIGHER INPUT IMPEDENCE . Due to its high input Impedence the input and output circuit is Physically Isolated.
- JFETs carry only small amount of current due to the reverse biasing of input terminals, so the input Voltage controls the output current.
That is why JFET is called as VOLTAGE DRIVEN Device.
- The Gain of JFETs is characterised as TRANSCONDUCTANCE ( the ratio of drain current and gate source voltage)
- The noise is much less in JFETs.
- JFETs are immune to radiation.
- It has negative temperature coefficient of Resistance , so they posses higher Temperature Stability
- JFETs provide HIGH Power Gain
- Good Frequency Response