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Electrical Network Topology | Electrical Network Graph

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Network Topology - Electrical Network Graph
Topology is the branch of mathematics in which we study those properties of geometrical configuration  of shapes which are unaltered under certain transformations as bending or stretching. In network topology we study the geometrical configuration of networks irrespective of the components present in the network (circuit).  The concept will explain later in this post. This is very easy topic and usually a part of first year of ECE discipline. It is important to understand this topic because it is helpful for solving complex circuits. This will helpful in later courses. At this point I would like to clarify difference between a circuit and a network. Network is an interconnection of elements (resistor,capacitors, sources, batteries etc). While a circuit is also a type of network providing a closed path or loop for the flow of current. In this context words network and circuit used interchangeably.

Key Concepts: What is meant by network topology …

Diode Approximations | Diode Models

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Description of Different Diode Models



You might come across the terms ideal and practical diodes. As a beginner these terms might confuse you. So, I think it is important to discuss the properties of an ideal diode and a practical diode.
Outline Discuss different diode approximation or diode models How does practical and ideal diode model differ from each other? Why do we need to learn the behaviour of an ideal diode?
Diode Models And IV Characteristics:The current voltage characteristics curve is shown in figure 7. Look at the graph, how much a practical diode deviates from ideal behaviour. An ideal diode is a piecewise linear device, while practical diode is a non linear device. Linear device means it's current voltage graph is a straight line. A diode is non linear because it's current voltage graph is non linear curve. For voltage values less than 0.7V, current is zero. Just above 0.7V, current increases rapidly. Current doesn't increase proportional to an increase in vol…

Diode Clampers - Biased & Unbiased Clampers

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Positive Clampers, Negative Clampers, Biased Clampers, Unbiased Clampers

Applications of Diode - Diode ClampersAnother popular diode based circuit is clamping circuit. A clamper circuit or network adds DC level to a given AC signal without any change in signal shape. A simple clamper circuit is shown below, comprise of a capacitor, diode and a resistor. Carefully choose the capacitance value. Time constant should large enough to maintain the shape of the output signal. The time constant can be increased by using larger capacitance values. Throughout this article I consider practical diode with drop of 0.7V.
V1 is the sinusoidal input VP is the peak voltage Vo is the output voltage

Outline: In this article I explain different types of clamper circuits, like biased clampers and unbiased clampers, positive and negative clampers. Positive Clamper:It clamps the incoming signal to an upward direction. See the circuit below (figure 1). The diode arrow points upward. It means the signal is going…

Diode Clippers | Diode Limiters

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Applications of diode - Diode Clippers

Clippers are also called amplitude selectors or slicer. A circuit arrangement used to cut off the part of the signal.  Diode clippers have ability to clip off unwanted parts of the waveform. Actually,we have set a reference point. Signal port lies above or below reference point clips off. You can think a half wave rectifier as a simplest form of clipper (see figure 1).

The basic components of clipping circuit is a diode and a resistor. In above circuit, negative half cycle completely eliminated. You can decide the clipping level of your own choice. To get the desired level of clipping, you have to add a DC source in series with the diode. These are called biased clippers.
Positive Clippers: It removes positive part of the input signal.
Negative Clippers: It removes negative part of the input signal.
Series Clippers: In series clipper circuits, diode is in series with input and output terminals.
Shunt Clippers: In shunt clippers, diode is in parallel w…