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I have a Power Supply of 24 volts and 2.5A.

I need something like that:


I need a power supply of 24V and almost 1500mA and another of around 8 volts and 500mA (to suplpy an Arduino). It is possible with this connection? Or I nees something like http://www.amazon.com/LM2596-Converter-Module-Supply-1-23V-30V/dp/B008BHAOQO/

How much the resistors would be?



marked as duplicate by Ignacio Vazquez-Abrams, Daniel Grillo, Passerby, Chetan Bhargava, Scott Seidman Jan 31 '15 at 15:25

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  • \$\begingroup\$ You need a 24v to 5V step down regulator. \$\endgroup\$ – Passerby Jan 28 '15 at 18:11

Using a switch-mode buck converter is the most energy-efficient method of doing what you want. The reason that I mention energy efficiency is that if you used resistors as per the image that you linked to, you will need to get rid of the excess heat generated. This amounts to (24V - 8V) * 0.5A = 8 Watts.

The dc buck converter that you linked to is also available on eBay for significantly less than Amazon's price. In fact, it's available on eBay for less cost than purchasing suitable resistors from Digikey.


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