Sam just shared a new tutorial: "How to Use DC Regulators/Converters"
So, you might have the best project in the world, an amazing idea and design, but no matter how clever your circuitry or how advanced your prototype is, unless you can power your project correctly, it all counts for nothing. Often you will need diffe…
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Hi Sam,
You write superbly, DC Regulators/Converters was informative and to the point. Some descriptions can be a bit too complex for the hobbyist, but yours are great :).
I’m retired from a career in Hydrology where we used electronic sensors to log pretty much anything and everything meteorological, plus gauging water levels and flows from natural catchments, wastewater ponds, groundwater systems, etc. Since then I’ve built and patented a Proximity Monitoring Unit to help Tugboats avoid overhead collisions. (C++ coding was done by a friend). Lidar sensors were 12V with a remarkable 100m range, controlled by an Arduino Mega board. Will see if I can attach a 2 page summary. Latest project is a weather station at home. Have attempted data delivery to Arduino Cloud but zero success :(. Next job will be motion detection to keep the kangaroos away from my wife’s garden. Let me know if this sparks any interest at all. (I’ll understand if no interest). Cheers. Glen T
Proximity Monitoring Sensor Prototype Brochure.pdf (587.8 KB)
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Hi @GLEN115595,
Welcome to the forum!
What a fascinating background, thanks for sharing! A 100 m Lidar on 12 V, paired with an Arduino Mega? Very cool.
Also feel your pain on the Arduino Cloud front, it can be a bit of a black box at times. If you’re still actively working on the project, feel free to make a post and maybe some interested makers can have a look.
And as for motion detection to keep kangaroos out of the garden, that’s both a classic Aussie problem and a great excuse for some sensor experimentation. PIR, mmWave, or even ultrasonic could all be fun options depending on your setup.
Again welcome and looking forward to seeing some of your projects pop up.
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Hi All
A bit of an add on to Sam’s tutorial.
A linear regulator such as a 78XX will also “clean up” a “dirty” higher voltage supply or one with a bit of ripple. As long as the lowest value of “dirt” or ripple is higher than the required output plus drop out voltage the required output will be clean and ripple free.
Another use. You need 7.5V but no 7.5V regulator. BUT you do have some 7805s. Hypothetical values here for simplicity but you can calculate using real ones.
Connect 5kΩ resistor across 7805 output (pin 3 to pin 2). Call it R1. Connect 2k5Ω resistor pin 2 to ground. Call it R2
There will be 1mA flowing through R1. The same 1mA will flow through R2 thus lifting the reference at pin 2 by 2.5V above ground.
The result: output pin 3 to ground 7.5V
You can get ant voltage you want above 5V up to the max allowed input voltage minus the drop out in this manner.
Or you could have a bin full of LM317s (or the low drop out version) which has a native output of 1.2V and do the same thing. Any voltage you need.
The 1A max current of these devices can be increased using power transistors but that is another story. Circuits for this are available in data sheets.
Or a cheap and cheerful no frills way to get most any voltage using a transistor.
High voltage to collector.
Zener or some reference from base to ground.
Resistor from collector to base, value chosen to adjust zener or reference plus base current.
Output from emitter will be zener or reference voltage minus 0.6V
Really just a common collector or emitter follower DC amplifier really. But it works and s a useful idea if a quick and easy voltage source is needed.
Cheers Bob
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