Adjustable Linear DC Power Supply PCB Design
A compact, 2-layer PCB implementation of an adjustable linear voltage regulator using an LM358 operational amplifier and a BD139 NPN pass transistor.This circuit takes a DC input voltage (e.g., $+15\text{V}$) and provides a smooth, adjustable output regulated by a reference Zener diode and negative feedback loop. Designed and routed using KiCad 8.0