Analog Electronics Notes PDF: Rectifier, BJT, FET & Oscillators Explained

Analog Electronics is one of the most important subjects for Diploma and B.Tech students. It forms the foundation of electronic circuits, amplifiers, and communication systems. In this article, Career FI India provides clear, exam-oriented notes to help you score better.

What is Analog Electronics?

Analog Electronics deals with circuits in which electrical signals vary continuously with time. These signals are represented by changing voltage or current and are widely used in radios, amplifiers, sensors, and power systems.

Rectifier: Working Principle and Types

A rectifier is an electronic circuit that converts alternating current (AC) into direct current (DC) using PN junction diodes.

• Half-Wave Rectifier
• Full-Wave Rectifier (Center-Tapped)
• Bridge Rectifier

Among these, the full-wave and bridge rectifiers are more efficient and commonly used in power supply circuits.

Clipper and Clamper Circuits

Clipper Circuit

A clipper circuit removes unwanted portions of an input signal above or below a specific voltage level.

• Positive Clipper
• Negative Clipper
• Biased Clipper

Clamper Circuit

A clamper circuit shifts the entire waveform upward or downward by adding a DC component.

• Positive Clamper
• Negative Clamper

Bipolar Junction Transistor (BJT)

Common Base (CB) Configuration

In common base configuration, the base terminal is common to both input and output circuits. It has low input resistance and high output resistance.

Current gain: α = IC / IE

Common Emitter (CE) Configuration

The common emitter configuration is the most widely used BJT configuration due to its high current and voltage gain.

Current gain: β = IC / IB

Field Effect Transistor (FET)

JFET

A JFET is a voltage-controlled device in which current conduction takes place due to majority carriers only. It offers high input impedance and low noise.

MOSFET and Its Types

MOSFET is widely used in VLSI, IC design, and power electronics applications.

• Enhancement Type MOSFET
• Depletion Type MOSFET
• n-channel and p-channel MOSFET

Oscillators in Analog Electronics

Hartley Oscillator

The Hartley oscillator uses inductive feedback and generates high-frequency sinusoidal oscillations.

Colpitt’s Oscillator

The Colpitt’s oscillator uses capacitive feedback and provides better frequency stability.

Frequently Asked Questions (FAQs)

Is Analog Electronics important for Diploma and B.Tech exams?

Yes, Analog Electronics carries high weightage in semester, diploma final, and competitive exams.

Which BJT configuration is most important?

The Common Emitter (CE) configuration is the most important due to its high gain.

What is the difference between clipper and clamper?

A clipper removes a portion of the signal, while a clamper shifts the signal level.

Is MOSFET important for technical interviews?

Yes, MOSFET basics are frequently asked in core electronics and VLSI interviews.

Are these notes suitable for self-study?

Yes, the notes are written in simple English and are suitable for self-study and revision.

Why Study from Career FI India?

• Exam-focused explanations
• Simple language for faster understanding
• Perfect for Tier-2 & Tier-3 college students
• Free high-quality study resources