Reuse a cellphone car charger as a switch-mode power supply.
Building your own switch-mode power supply (SMPS) can be fraught with disappointment and frustration. Even with modern ICs designed to make SMPS design easier, you can still run into issues with PCB layout and circuit efficiency. This project demonstrates how you can build your own SMPS by using a charger you may have stuffed in a drawer somewhere.
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