Why is there a diode connected in parallel to a relay coil?

The purpose of a diode connected in parallel to a relay coil (flywheel diode or freewheeling diode) is to avoid damaging some nearby components sensitive to high voltage.

Power Supply block Diagram

Many electronic circuits need a direct current (DC) voltage source, but what we commonly find are voltage sources of alternating current (AC). In order to achieve a direct current voltage source, the alternating current input must follow a conversion process.

Universal Electric Motor – Constitution, Operation, Speed

The universal electric motor is so named because it is the only motor that can be connected to both alternating current and direct current.

Transformerless Power Supply circuit

This circuit is designed to be connected to a specific circuit because it can give a maximum and minimum possible electric current

Transistorized Voltage Regulator Why use a transistorized voltage regulator? If we use a half or a full-wave rectifier we can convert an AC voltage in a DC one. This converted voltage is unregulated, because the output voltage is not constant and can change due to variations of the load value. To reduce these variations we connect […]

What is the Dielectric constant / Relative Permittivity? (Capacitor)

The dielectric constant is the ratio of the permittivity of a substance to the permittivity of free space. It is a dimensionless physical constant

How does a Zener diode voltage regulator work?

Design method. Determination of the voltage, power of the zener diode and of the limiting resistor Rs

Voltage regulators

Voltage regulators (linear, switching) provide a stable and fixed voltage output to give energy to electronics circuits from an unregulated power source

Capacitors in series – Capacitors in parallel.

How to obtain the equivalent capacitance of series capacitors and parallel capacitors? Formulas and examples

Electrolytic Capacitor

Electrolytic capacitors have been developed to achieve large capacities in small physical dimensions. To achieve this large capacity, a special dielectric is used.

Amplifiers and Amplification

Amplifiers are circuits that are used to increase an input signal, thus you can obtain an output signal with much greater amplitude than the original one. Amplification is the process to increase the magnitude of a signal, generally using an amplifier.

What is an LDR – Photoresistor?

LDR (Light Dependent Resistor) is light sensitive resistor whose resistance changes with the light intensity that falls upon it.