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Using TPS2113A power mux for robot power dock


I have a Raspberry Pi B+ based robot built using Pololu parts and I want to add a power dock to charge the 5V battery pack (its a 5V USB battery pack) and also power the RPi.

Will the TPS2113A power mux switch power fast enough so as not to reset/brownout the RPi?
The datasheet does have a table for switching characteristics, but I am not sure if those are sufficient and what are the correct specs to be looking at.

I was also planning to use a separate mosfet switch to turn on battery charging for after the RPi has been switched to the power from the dock.




The TPS2113A power multiplexer seamlessly switches between power supplies and should be fast enough for the Raspberry Pi. However, I am not sure how you plan on adding your charging circuit to the system. If you post a diagram showing your plan for connecting your charging circuit, I might be able to give you additional feedback.

- Jeremy


Thanks for that information! Sounds like the power mux should work great for my case.

I have attached a bad doodle of what I had in mind.

The battery pack I am using is similar to one of these, and has a micro usb charging port. When connected to a charger the 5V output gets automatically turned off.

I am also worried about the mechanical design and electrical coupling for the dock since I will probably be drawing more than 1A at 5v while powering the raspberry Pi and charging the battery. Definitely don’t want to burn down the house :open_mouth: with my robot. Any pointers on robot charging dock design would also be appreciated.


Your diagram and plan seem reasonable. For the charging station, you will probably want to mechanically/physically prevent the robot from connecting power backwards.

Good luck on your project. You might consider posting about it in the Share Your Projects section of our forum.

- Jeremy