The scenario
Designing the power stage for an FPV drone flight controller, where a 6S LiPo feeds a 4-in-1 ESC and a current sensor must interface cleanly with the MCU.
What is in this drawing
Read the decisions behind it.
01
Place the current-sense shunt on the battery return path so the op-amp measures a low-side differential voltage without disturbing ESC ground.
02
Use a separate 5V BEC from ESC power to supply the MCU and current-sense amplifier, with local bulk and decoupling capacitors.
Reuse this schematic for any quadcopter or drone where a single 4-in-1 ESC drives four motors and battery current is monitored by a flight controller ADC.
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