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A-Star 32U4 Robot Controller LV With Raspberry 4 and 2 USB Keys

I am working on an autonomous vehicle. I try to use the A-Star 32U4 SV and Raspberry bridge with a Raspberry 4 and two usb keys (Coral accelerators). Each key needs at least 500-700 mA. The Raspberry 4 also needs a lot of power. The Raspberry spec recommend using a good quality 2.5A power supply if downstream USB peripherals consume less than 500mA in total. I suppose I need at least 3A.

I am searching the best configuration to power the raspberry with the A-Star.
I tried to use an ESC with a 6V or 7.4V/6A BEC. I connected the BEC to the Power In inputs of the A-Star. This is not working. I think I may hit the 1.8A limit of the A-Star’s TPS2113A.

I am going to use an external UBEC 5V10A to connect the 2 batteries (2*3s) to the USB power source of the A-Star. The motors and the servos (6V) of the vehicle are powered by the BEC of the ESC. Does anybody know if this is the best practice?

Thank you!

Hello.

It sounds like you are expecting your Raspberry Pi 4 and your two USB devices to draw upwards of 3A. If that is the case, you should not power them through the A-Star Robot Controller’s onboard regulator. Instead, you might consider powering the Raspberry Pi through its typical USB power connection from a source that can source enough current for it and its connected devices.

Brandon

Hi - Yes. This is what I did. I used an UBEC 10A/5V for the raspberry and the ESC’s BEC for the A-Star.
Thank you for your help!

N