Basic Electronic Components

Over the last few decades’ electronics technologies and product development have been growing and rapidly have become more and more complex. Knowledge of electronic components is essential to build successful electronic products.

Some of the most commonly used electronic components are resistors, capacitors, inductors, diodes, LEDs, transistors, crystals and oscillators, electromechanical components like relays and switches, ICs, and connectors. These components have leads/terminals and are available in specific standardized packages, that the designer can choose to suit his application. SMT (surface mount technology) and through-hole are the two types of mounting techniques used to place components on a PCB.

Types of electronic devices

Electronic devices can be divided into two major kinds: Passive and Active devices based on their functionality.

Passive devices

Generally, resistors, capacitors, inductors, are specified as passive devices.

Resistors

The resistor is a passive electrical component whose function is to introduce resistance to the flow of electric current in an electrical circuit to limit the current. The magnitude of the opposition to the flow of current is called the resistance of the resistor. A larger resistance value indicates a greater opposition to current flow. The resistance is measured in ohms (Ω).

Different types of resistors by size and form

• Through-hole resistors
• Surface-mount resistors SMD/SMT

Different types of resistors by application

• Common resistor: used in current limiter, setting biases, voltage dividers, pull up, filtering, termination resistors, load resistors, etc.
• Precision resistor for voltage feedback circuits, voltage references.
• Current sense resistors
• Power resistors

Resistor selection parameters

While selecting any resistor in the circuit, the designer needs to consider the following parameters based on the application and real-estate available on the printed circuit board.

• Resistance value(R),
• Power (Wattages) dissipated across it,
• Tolerance (+/- %)
• Size based on available space on PCB.

Resistor manufacturers: AVX, Rohm, Kemet, Vishay, Samsung, Panasonic TDK, Murata, etc.