Fundamentals of Electronic Systems and Components

Electronic Systems and Signal Processing

An electronic system captures information from the outside world (such as sound or light), converts it into electrical signals, processes it, and transforms it into another energy source to produce a specific effect.

Types of Signals

• Analog Signals: Continuous signals that can take an infinite number of values.
• Digital Signals: Discrete signals that exist only at specific moments and take specific values, usually transmitted in binary.

Capacitors

A capacitor consists of two parallel metal plates separated by air or another material called a dielectric. Its function is to store electrons and release them when necessary. The amount of energy it can store is called capacitance, measured in farads.

• DC Behavior: Current flows while the capacitor is charging, but it blocks current once fully charged.
• AC Behavior: Allows the flow of energy at all times.

Inductors (Reels)

An electrical component that generates a magnetic field when current flows through it, or generates an electric current when approached by a magnet.

• Induction: Occurs when a coil creates a magnetic field in a second coil.
• Inductance: A coil induces current within itself.

Transistors

Transistors are widely used as electrical signal amplifiers or switches. Bipolar transistors consist of three layers: a base, an emitter, and a collector.

• NPN Transistors: A P-type semiconductor layer between two N-type layers.
• PNP Transistors: An N-type semiconductor layer between two P-type layers.

Operation is based on the base current; the current flowing between the emitter and collector is much larger than the base current. Small variations in the base intensity cause large variations in the collector intensity.

Operating Methods

• Cut-off: No current is supplied to the base, cutting the current path.
• Saturation: The base receives enough current to allow maximum flow between the collector and emitter.
• Active: The base receives a controlled amount of power.

Sensors and LEDs

• Sensors: Devices that detect environmental changes and transform them into electrical signals.
• LEDs: Components that convert electrical power into light, often used as indicators.