# Welcome to Electronics Area

## Boolean Algebra – Introduction and Rules

Boolean Algebra is a tool to reduce logical expressions. It is the mathematics of logical expressions, which was presented by George Boole in 1854.

## Crystal Oscillators – Piezoelectric Oscillator. Equivalente circuit

The Crystal Oscillators (Piezoelectric Oscillator) A quartz crystal has a property called: piezoelectric effect. This effect causes, by applying a mechanical pressure on the surface of the crystal, that a voltage is developed…

## LC Oscillator – Inductance – Capacitance Oscillator

LC oscillator: Inductance – Capacitance Oscillator A simple oscillator can be built with an amplifier stage and an inductive-capacitive network (LC) to provide an offset of -180° The oscillation frequency can be freely adjusted…

## Phase Shift Oscillator

The Phase Shift Oscillator The phase shift oscillator, whose basic structure is described in the picture 1.a  has a a negative gain amplifier (-K) and a feedback network consisting of a third order…

## Wien-bridge Oscillator with Op Amp

Wien-bridge Oscillator using Op-Amp The Wien-bridge oscillator, as shown on the basic outline of the diagram below, consists of an Operational Amplifier (OA) in a non-inverting configuration with gain 1+R2/R1 and a RC…

## Nonlinear Amplitude Control of a Sinusoidal Oscillator

Nonlinear Amplitude Control of a Sinusoidal Oscillator In any practical oscillator, the loop gain (ßA) must be slightly greater than unity to prevent that the tolerance parameters of components, aging, temperature…

## Sinusoidal oscillators – Basic principles

Sinusoidal Oscillators Sinusoidal oscillators play an important role in electronic systems that use harmonic signals. Despite that, in many instances are known as linear oscillators, it is necessary to use some non-linear…

## Signal Generators

Introduction to Signal Generators The function of a signal generator is to produce time a dependent signal with some special characteristics of frequency, amplitude and shape. Sometimes these features are controlled externally throughout control…

## MOSFET transistor – Saturation and breakdown regions

Saturation region of a N channel Mosfet transistor The NMOSFET transistor behaves as a voltage controlled current source VGS. Check the following equations: where ß = K (W/L) In this region, the quadratic…

## JFET Saturation and Breakdown regions

JFET Saturation and Breakdown regions The JFET Saturation region In this region the JFET has some linear features that are used in amplification. These features are similar to those of a BJT in the…

## JFET Cutoff and Linear regions

JFET Cutoff and Linear regions JFET Cutoff region In this region the current flowing from the Drain to the Source terminals of the JFET is zero (ID = 0). In this case, the voltage between…

## Microwave Oven History

Microwave Oven History The microwave oven was discovered in 1947  by Percy Spencer. Mr. Percy  Spencer, an engineer of the Raytheon Company, was carrying in his jacket pocket a bar of…