Connecting Dynamixels MX106R with PH42-020: voltage compatibility

Hello Robotis community,

I am using PH42-020 and MX106R with Protocol 2 firmware.
I am attempting to daisy chain both motors using U2D2 on the U2D2 power board. The connection would be:

U2D2 --(1)–> PH42-010 --(2)–> MX106R

connection --(1)–> will be using the JST 4 pin connecting cable
and connection --(2)–> will be using the JST to Molex converting cable

I need a bit of advice on how I can power PH42-020 with 24V and MX106R with 12V. Could I just intercept pin1 and pin2 in connection --(2)–> with a 24V-12V voltage converter? Or is there any better ways to do this? Thanks so much.


Thanks so much

Ok I will give my thoughts.

If you need 2 different voltages on your system (3 in fact as you have your micro controller too) then there is a couple of options.

  1. as you suggested you use a voltage converter (buck converter) to change your voltage. You will need to make sure your buck converter can handle the amps you need to supply.

  2. have more than 1 power supply, not sure how your powering this system, battery or mains. If you use more than 1 power supply then you will need a common ground.

  3. choose dynamixels that all run off the same voltage. Best choice as then you don’t have to contend with different voltage supplies.

The dynamixels have 3 wires, 1 data line, power line and a ground line. The data line will communicate on 3.3v then power line voltage will depend upon the needs of the selected dynamixel then the ground will be common to everything.


Thanks so much! Youre right, there would be three. But I might go for option 1. So I need to confirm, I could just buck the voltage at pin1 and pin2 between the two motors right (at connection --(2)–>) ?

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I would assume you can put a buck converter between the 2 motors on the power lines and it should work. The buck converter will need both ground and power to go through it and you will need to choose a buck converter that can handle the amps as well as the needed input and output voltages.