Inrush current/Switch-ON surge is the maximal instantaneous input current drawn by an electrical device when first turned on. Inrush current is much higher than the load’s steady-state current and that’s the source of many problems such as fuse blowing up, load failure, load’s lifetime reduction, sparks at the switch contacts … etc. I tried to address this problem with an easy, however effective solution. I have introduced two circuits for both AC and DC loads.
YouTube: Soft Starter Circuits (Inrush Current Limiter) for AC and DC Loads - YouTube
References
Article: Inrush Current Limiter (Soft Starter) for AC/DC Loads - Technology - PCBway
[1] DB107 Datasheet: https://www.diodes.com/assets/Datasheets/products_inactive_data/ds21211_R5.pdf
[2] BD139 Datasheet: https://www.onsemi.com/pub/Collateral/BD139-D.PDF
[3] DB107 Schematic Symbol and PCB Footprint: DB107TB footprint, schematic symbol and 3D model by SMC Diode Solutions
[4] BD139 Schematic Symbol and PCB Footprint: BD13910STU footprint, schematic symbol and 3D model by onsemi
[5] CAD Plugins: Library Loader help - SamacSys