Project Overview: 2S LiPo High-Current Power Box

This circuit is a high-performance power distribution system designed for large-scale RC models. It manages power from dual batteries to drive up to 16 High-Voltage (HV) servos while providing redundancy and electronic switching.

Key Technical Features

• Dual Battery Redundancy: The input stage features two "Ideal Diodes" (U$1, U$2). These allow for a dual-battery setup (2S LiPo, ~8.4V) with minimal voltage drop and prevent back-charging if one pack fails or has a lower voltage.
• High-Current Power Path: Utilizing multiple IRF4905 P-Channel MOSFETs in parallel, the board is designed to handle a continuous load of 20A, ensuring stable current delivery to 16 HV servos during high-torque maneuvers.
• Electronic Switching (Soft-Switch): * The circuit includes a logic stage (BSS123 N-FETs) that controls the main power MOSFETs.
• Compatibility: The "SW" header is designed to interface with Jeti RC switches or Magnetic switches. It uses a "fail-on" logic where the system remains powered if the switch signal is lost, enhancing safety.
• Servo Distribution: The output rail (VSERV) distributes power across 20 headers (JP1-JP20), supporting 16 primary servos with integrated decoupling capacitors (C1, C2, C3) to filter voltage spikes and electrical noise.

Schematics

PCB

The PCB can be bought directly from this project page

The PCB was kindly sponsored by PCBWay and is as usual of excellent quality. It's cheap, delivered very fast and so professional looking!

and if you are new to PCBWay please use this affiliated link : https://pcbway.com/g/o35z4O

As you can see "big" tracks are exposed to be reinforced either with solder or (better) with copper wire. Doing this will increase drastically the current capcabilities of this board. It will sustain up to 20A with a total of 16 servos powered with 2s lipo packs.

Work in progress, please stay tuned