24V Servo Control Board?

Hi Guys,

I am working at a research institute. We have a 10 year old SCARA arm that was left to us by another group. Sadly it isn not in working order. The problem is that the software that is supposed to drive the arm no longer reckognize the machine. Appereantly there is sth wrong with the control electronics. I could design a pcb that could propably drive it but we dont want to invest that much time in it. So we were thinking maybe we can can drive the servos with an arduino. The problem is that the servos use 24V and all the online material that I find are for 5V. So I was thinking i could copy the PWM signal from the Arduino with a Mosfet or BJT to the machine. But I am not sure if my logic to approach the problem is the right way. Maybe someone here knows a professional board that could do this task. Any advice on the matter would be appriciated as this is actually my first time working seriously with servo motors. Here is the datasheet of the servo at hand "https://www.comoso.com/uploads/products/downloads/Schunk_Comoso_PRL_Manual.pdf"

Best Regards,


I think the reality is the time it would take for to do either of your suggestions would be better spent discovering and repairing the existing master controller board.


I may have a solution for you.
I just developed a 32-PWM board to drive my 32 MOSFET board.
The 32-PWM comes from two SX1509 chips, the MOSFETs are rated for 30V and would effectively invert the PWM signal, so you'd have to take that into account.
Here is a picture of the first unit Ididn't realize it was so blurry when I took it), driven from a 1284P board as the user wanted more IO than an Uno and with screw terminals. (DS1307 RTC, RS232 for the 2nd hardware serial port, SD card are also provided).

Sorry the picture is a little blurry. I am waiting to hear how it works, I didn't have any working SX1509 code ready when I shipped it.

I suspect the Elco Jacobs shift-PWM code with TPIC6C595 or TPIC6B595 high voltage rated outputs might also work.

(don't know why the forum flipped this upside down). (and then resized it. Lovely).

Hi Paul,

There was already a master Student trying exactly that. But he couldnt do it that is why my boss gave the task to me. I already have other projects i need to deal with so I was hoping for a quick solution with an arduino. I will certainly consider your suggestion. I will be making the first tests tomorrow. Thanks for the reply!



Thanks! That is certainly a very very good starting point :slight_smile:
I will take a look into the datasheets first thing in the morning.