In this article I will tell you how to get shorter relay switching times and how to minimize relay current consumption. The same exact things apply to solenoids and solenoid valves.
You need to use a transistor because either relay you want to control needs a higher voltage than your microcontroller can provide, or relay’s current demand is too high. Although some microcontrollers can give enough current to switch a relay, but most of them is incapable of doing that.
And the diode in parallel with relay coil (or solenoid coil) is needed to suppress the flyback voltage that occurs when transistor is switching-off and magnetic field stored in coil collapses. That flyback voltage can reach hundreds of volts, which can completely destroy the driving transistor.
Using Relays (Tips & Tricks) - [Link]
A Beginner’s Guide to the MOSFET @ ReiBot.org. [via]
If you need to switch high current and or high voltage loads with a micro controller you’ll need to use some type of transistor. I’m going to be covering how to use a MOSFET since it’s a better option for high power loads. This guide will be just a brief introduction that will discuss how to drive a mosfet in a simple manner with the ultimate goal of making it act like an ideal switch.
Refer to the N or P channel basic wiring schematics and remember the three pins: Gate, Drain, and Source. When I mention something like Gate-Source potential difference, I’m talking about the difference in voltage between the two pins.
A Beginner’s Guide to the MOSFET - [Link]
Bill explains the basics of Phase Lock Loops(PLLs) and their uses.
Phase Lock Loops 101 with Bil Herd – [Link]
Resistor basically is used as a current limiter or current/voltage divider in electronics circuit. Resistor value is measured in Ohm (Ω) name after George Simon Ohm who first to lay down the fundamental relationship among Resistance, Current and Voltage. This relationship is known as Ohm’s law; basically the Ohm’s law say that the current flow in the closed circuit is equal to the voltage divided by the total resistance occur in the circuit or we can write the Ohm’s law equation as follow:
Basic Resistor Circuit - [Link]
Resistor is one of the electronic component that used in electronic design for controlling the flow of electric current. The more it resists the small the electric current will flow and vice verse. The resistance value is measured in ohm which is named after Georg Simon Ohm who first define the well known Ohm law, the fundamental relationship among Resistance, Current and Voltage. The symbol of resistance is the Greek letter omega (Ω).
How to read the Resistor value - [Link]
I decided it would be easiter to explain AC and DC current if the user already knew how to use and oscilloscope. Explaining how to use an oscilloscope is easy if the user already knows what DC and AC current is. I think the video worked out as a fast paced tutorial for both subjects.
AC vs DC Explained and How to Use an Oscilloscope – [Link]
So I have seen a lot of people asking where is a good place to learn about electronics. I think it is about time that someone made an instructable about it. In this instructable I will cover some of the main electronics components, their uses and what they look like in schematics. I would like to request the members who are good with electronics to help out; if I missed a component, tell me I missed it, if I got some information wrong, tell me, please.
Electronics made easy – [Link]
We continue the introductory series with MOSFETS (Metal Oxide Semiconductor Field Effect Transistor)
We will be looking at both the DE MOSFET and the ENHANCEMENT MOSFET
Introduction to MOSFETS – [Link]
Most of microcontrollers work within 5 volt environment and the I/O port can only handle current up to 20mA; therefore if we want to attach the microcontroller’s I/O port to different voltage level circuit or to drive devices with more than 20mA; we need to use the interface circuit. One of the popular method is to use the Bipolar Junction Transistor (BJT) or we just called it transistor in this tutorial. I have to make clear on this BJT type to differentiate among the other types of transistors family such as FET (Field Effect Transistor), MOSFET (Metal Oxide Semiconductor FET), VMOS (Vertical MOSFET) and UJT (Uni-Junction Transistor).
Using Transistor as a Switch – [Link]