The scenario
Build a variable DC power supply for prototyping, providing a main adjustable output up to 15V and a fixed 5V USB port for powering microcontrollers.
What is in this drawing
Read the decisions behind it.
01
Using LM317 for adjustable output with potentiometer voltage divider
02
Adding 7805 regulator for fixed 5V USB output
When you need a bench power supply from AC mains with both variable and fixed 5V outputs.
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