https://www.adafruit.com/product/2236
5.0V 250mA Linear Voltage Regulator - L4931-5.0 TO-92 : Adafruit Industries, Unique & fun DIY...
Need a nice little 5V regulator? We rather like the very-low-dropout L4931 from ST! This little guy will help you get your 5.5-20V battery or wall adapter down...
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https://www.electronicsforu.com/videos-slideshows/videos/buck-converter-vs-linear-voltage-regulator-3
Buck Converter vs Linear Voltage Regulator
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