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Showing posts from March, 2020

RC Current Sensor

Most of the RC current sensor designs are using a hall effect-based current sensor, like the ACS758. In this project I would like to try something different (more difficult?) and use a conventional high-side current sensor to achieve the following goals:
Maximum 60A continuous current sensing capabilityMaximum 5S (18.5V) LiPo battery inputSend telemetry data (current, voltage, power and capacity) to my Jeti DS-24 transmitterLightweight, small (and cheap) design Hardware design In the project I used an STM32G431KBU which is a powerful 32bit processor in a small package (LQFP32). It is too much for this job, but I bought them in bulk because I would like to use them in other projects too.

The design based on a high-side current sense amplifier: MAX4081. The current from the battery to the speed controller flows through a precision high power current-sense resistor (CSS2H-3920R-L200FE) which is sensed by the MAX4081. The current-sense resistor dissipates its own I2 × R loss, so for 60A i…