Junction Field Effect Transistor (JEET)
Subject and UNIT: Electron Devices and Circuits: Unit II: (b) Junction Field Effect Transistor (JEET)
• Fig. 3.9.12 shows common source amplifier with self biasing having unbypassed Rs.
Subject and UNIT: Electron Devices and Circuits: Unit II: (b) Junction Field Effect Transistor (JEET)
• In the second chapter, we described the operation of JFET, and analysed and designed the d.c. response of circuits containing JFET. In this chapter we emphasize the use of FETs in linear amplifier applications.
Subject and UNIT: Electron Devices and Circuits: Unit II: (b) Junction Field Effect Transistor (JEET)
Comparison of BJT and JFET
Application | Junction Field Effect Transistor
Subject and UNIT: Electron Devices and Circuits: Unit II: (b) Junction Field Effect Transistor (JEET)
• Let us consider the drain characteristics of FET as shown in the Fig. 3.7.1 In this characteristics we can see that in the region before pinch off voltage, drain characteristics is linear, i.e. FET operation is linear.
Junction Field Effect Transistor (JFET)
Subject and UNIT: Electron Devices and Circuits: Unit II: (b) Junction Field Effect Transistor (JEET)
• The intersection of this straight line with the transfer curve in the region to the left of the vertical axis is the operating point (Q point).
Solved Example Problems | Junction Field Effect Transistor (JFET)
Subject and UNIT: Electron Devices and Circuits: Unit II: (b) Junction Field Effect Transistor (JEET)
• Different biasing circuits of JFET are : • Fixed bias circuit • Self bias circuit • Voltage divider bias circuit
Solved Example Problems | Junction Field Effect Transistor
Subject and UNIT: Electron Devices and Circuits: Unit II: (b) Junction Field Effect Transistor (JEET)
A p-type gate is then diffused into the n-type channel. In this device, a slab of n-type semiconductor is sandwiched between two layers of p-type material, forming two p-n junctions.
Drain and Transfer Characteristics
Subject and UNIT: Electron Devices and Circuits: Unit II: (b) Junction Field Effect Transistor (JEET)
The important characteristics of JFET are drain characteristics and transfer characteristics. The following section explains these characteristics in detail.
Junction Field Effect Transistor
Subject and UNIT: Electron Devices and Circuits: Unit II: (b) Junction Field Effect Transistor (JEET)
In JFET, the p-n junction between gate and source is always kept in reverse biased conditions. Since the current in a reverse biased p-n junction is extremely small, practically zero; the gate current in JFET is often neglected and assumed to be zero.
Structure of Channel
Subject and UNIT: Electron Devices and Circuits: Unit II: (b) Junction Field Effect Transistor (JEET)
• Heavily doped electrodes of p type material form p-n junctions on each side of the bar. The thin region between the two p gates is called the channel. Since this channel is in the n type bar, the FET is known as n-channel JFET.
Subject and UNIT: Electron Devices and Circuits: Unit II: (b) Junction Field Effect Transistor (JEET)
• The three terminals of FET are named as Drain (D), Source (S) and Gate (G), as shown in the Fig. 3.1.1. Out of these three terminals gate terminal acts as a controlling terminal.
Electron Devices and Circuits
Subject and UNIT: Electron Devices and Circuits: Unit II: (b) Junction Field Effect Transistor (JEET)
Electron Devices and Circuits: Unit II: (b) Junction Field Effect Transistor (JEET) : Syllabus, Contents