But Don’t Pass Up Conventional Electronics
Trying It Out
Once the temperature switch is calibrated for a specific
temperature, you can test the switch by heating the LM34
with a hair dryer. You can hook up an LED on the output
(Vout). Once the temperature reaches the specified point,
your LED should go on and stay on until the temperature
drops again.
Just like the flashing LEDs, this circuit is relatively
easy to build without a microcontroller. You can use this
circuit as it is or modify it to suit many different purposes
that you may have. You can also learn a great deal about
how comparators work. At the very least, it will hopefully
spur many ideas on how you can make comparators work
for you.
My advice to anyone getting started in microcontrollers
and electronics is to get a breadboard, some basic
electronic parts (get a grab bag or two), and start
experimenting.
To start experimenting, keep reading Nuts & Volts
and grab a book or two on the basics of electronics. Some
of the best books I found for beginners are the Forrest
Mims books from RadioShack. My Forrest Mims book is
very old and beat up, but it’s never very far from me when
I experiment. There are also some really great websites out
there that can help. Just like I said at the beginning of this
article — microcontrollers are great! Try not to use them as
a crutch and, instead, use some of those conventional
electronics that have been around for years. Happy project
building! NV
Easy as Pie
These two circuit examples can be used as stand-alone circuits or they may be used in conjunction with
other circuits. They can completely replace the use of a
microcontroller. At the very least, these circuits can take a
significant load off of your microcontroller-based project.
The examples I have shown you are only part of what is
available for the electronic hobbyist; they are only my
ideas and certainly there are many others.
About the Author
Ever since I was about 10 years old, I have been interested
in electronics. I went to school to become an electronics
engineer, but decided to keep my electronics interest as a
hobby instead, so I went into computer programming.
Currently, I am a web developer and I love what I do. My
favorite electronic device is the microcontroller because it
involves my two loves (electronics and programming).
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