First, what are electrical circuits? They are components of any electronic system that allow the operation of any technological application. Electrical circuits are made up of a set of interconnected components that allow the controlled flow of electric current, whether high or low intensity. Different types of circuits are used for various fines and have distinctive characteristics in terms of behavior and applications.

Among the many categorizations of circuits and their types, we can find one that stands out in Circuit Theory, and it is the one that classifies them into linear circuits and non-linear circuits. Its use is widespread in all sectors or areas of society, such as communication, power electronics, medicine and computing, among others. But better let's look at them in detail.

Circuitos lineales:

Veamos un ejemplo concreto:

Datos: R = 100 Ω, V = 10V

Utilizaremos la Ley de Ohm para hacer el cálculo.

I = V/R = 10V/100Ω = 0.1A

Linear circuits:

Linear circuits are defined as those in which the input and output signals have a linear relationship. This means that if we plot the input and output values ​​on an (X,Y) graph, the result will be a straight line. These circuits are made up of linear elements, such as resistors, inductors and capacitors. A linear circuit must also comply with the principles of superposition and homogeneity, and exhibit properties such as attenuation and constant phase. In other words, we could say that, in a linear circuit, its parameters of electrical resistance, capacitance, inductance and gain do not vary, even if we modify the current or voltage of the circuit. Linear circuits are primarily found in high-fidelity audio system, data transmission, signal processing, and automatic control applications.

Let's look at a concrete example:

Let's consider a simple circuit formed by a 100 ohm resistor connected to a voltage source. Here we want to calculate the current flowing through the resistor.

Data: R = 100 Ω, V = 10VD

We will use Ohm's Law to do the calculation.

I = V/R = 10V/100Ω = 0.1A

We can conclude that the current flowing through a resistor is directly proportional to the applied voltage and is determined by the value of the resistance.

Circuitos no lineales:

I = (Vin - Vd)/R = (Vin - 0.7V)/10Ω

Nonlinear circuits:

Unlike linear circuits, nonlinear circuits have a nonlinear relationship between the input signal and the output signal. These circuits can exhibit complex behaviors, such as harmonic generation, distortion, and non-symmetrical response. In this type of circuit, its parameters, such as waveform, resistance and inductance, vary depending on the input current and voltage. A circuit is classified as nonlinear if it contains at least one nonlinear element, such as diodes, transistors, and transformers. They are essential in applications such as signal amplification, modulation and demodulation, and are mainly used in audio systems, telecommunications and radio frequency electronics.

Let's also look at a concrete example:

Let's consider a circuit composed of a diode with an internal resistance of 10 ohms connected to a voltage source. We want to determine the current through the diode as a function of the input voltage.

We will use the formula for the simplified model of the ideal diode, assuming that the diode turn-on voltage Vd is 0.7 volts.

I = (Vin - Vd)/R = (Vin - 0.7V)/10Ω

For Vin = 0.2V: I = (0.2 - 0.7)/10 = -0.05A (negative current, meaning the diode is reverse biased)

For Vin = 0.4V: I = (0.4-0.7)/10 = -0.03A (equally reverse biased)

For Vin = 0.6V: I = (0.6 - 0.7)/10 = -0.01A (also in inverse)

For Vin = 0.8V: I = (0.8 - 0.7)/10 = 0.01A (it is now positive, forward biased and current flows in the expected direction)

For Vin = 1.0V: I = (1.0 - 0.7)/10 = 0.03A (also direct)

We can conclude that the current through the diode varies nonlinearly with the input voltage. It is important to note that this ideal diode formula is an approximation and therefore not precise.

What did you think of the theory? In summary, circuit theory is a fundamental field in electronics that allows us to understand and analyze the behavior of electrical circuits. By exploring and mastering these concepts, experts can contribute to the advancement of technology in numerous fields, from consumer electronics to renewable energy, medicine, and more.

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Clarify that the main image was created with Bing AI and edited in Canvas.