During purchasing a JFET for a particular application we need to check the specifications of the device. These specifications are provided by manufacturers. The followings are the parameters used to specify a JFET and these are Gate Cut Off Voltage (VGS(off)) Shorted Gate Drain Current (IDSS) Transconductance (gmo) Dynamic Output Resistance (rd) Amplification Factor (μ) … Read more
Both n channel JFET and p channel JFET can be used as a switch. Before going to the actual operation of JFET as a switch we will discuss the basic properties of a switch and then we try to correlate those properties of a switch with the operation of JFET. This will help us to … Read more
There are two types of junction field effect transistor. N channel JFET P channel JFET Let us discuss the characteristics of n channel and p channel transistor separately one by one for better understanding. Characteristic of N Channel JFET We know that there is a channel of n-type semiconductor material in n channel JFET. The … Read more
Before going to actual topic let us know what is a pinch-off voltage of a junction field effect transistor because it takes a vital role to decide the biasing level of a junction field effect transistor. Pinch Off Voltage In an n channel JFET, if we apply positive potential at drain terminal keeping the source … Read more
The bipolar junction transistor is a current controlled device. In this transistor mainly base current controls the operation of the device. In BJT both minority and majority carriers are involved in the operation. On the other hand, a junction field effect transistor is a voltage controlled device, and only majority carriers take part in the … Read more
When we apply an alternating signal to the gate terminal of a JFET, that would be amplified in the drain circuit. The proper amplification of a gate signal depends on proper biasing of both gate and drain section of the JFET. Proper biasing ensures that the JFET is being operated in the active or saturation … Read more
Field Effect Transistors (FETs) are used as Analog Switches The application of FETs as the switches in analog circuits is a direct consequence of their mode of working. This is because when the Gate-Source voltage, VGS is zero, n-channel FET will operate in saturation region and will act like (almost) a short circuit. Thus the … Read more
Junction Field Effect Transistor is a semiconductor device in the family of field effect transistor. The field effect transistor is the type of transistor which being operated by the electric field applied across the junction of the device. There are mainly two types of field effect transistor. Junction Field Effect Transistor or JFET and Metal … Read more
Junction Field Effect Transistors (JFETs) are a type of FETs (high input impedance devices) which have three terminals namely, Source (S), Gate (G) and Drain (D). These devices are also called voltage controlled devices as the voltage applied at the gate terminal determines the amount of current flowing in-between the drain and the source terminals. … Read more