0
\$\begingroup\$

For my robotics project I am powering the arduino with a 12v 250mA source. I am using a DC motor l298 breakout board by iTead that allows a power supply of 5v to around 46v for DC motors. I am also using a geared DC motor that has operating voltage between 3v and 7.5v. enter image description here I drew this up (imagine the bulbs are the arduino and breakout, couldnt get them on circuits.io) Can I use a 6v regulator for breakout without any issues? And also I see people use capacitors alongside regulators to reduce spikes or something but I did not know what to implement so could someone explain that as well? cheers.

Update: This Is what the circuit is of on circuits.io Also there is no 6v regulator in it so i used a 5v enter image description here

\$\endgroup\$
  • \$\begingroup\$ 12V 250mA? It won't be enough for your setup with a high certainty, even without knowing your specs.. Especially with a linear regulator which will drop it like two times... \$\endgroup\$ – Eugene Sh. Aug 8 '16 at 14:49
  • \$\begingroup\$ playground.arduino.cc/Learning/WhatAdapter Arduino say that 9v - 12v is recommended and the current in my setup is probably bigger than 250mA but I dont know how much it acctually is \$\endgroup\$ – Don Grey Aug 8 '16 at 14:53
0
\$\begingroup\$

Can I use a 6v regulator for breakout without any issues?

Well, with motors, I would reccomend against it. The motors (Especially if under load) will draw loads of current, and that will have to pass through the regulator, which will cause it to get very hot, as the effeciency of linear regulators is quite low. I would only really reccomend regulators in projects that aren't current intensive.

And also I see people use capacitors alongside regulators to reduce spikes or something but I did not know what to implement so could someone explain that as well?

There are two types of capacitorrs that you may be referring to. Brown-out Capacitors will protect your circuits from brown out from using too much power, typically store enough energy for 1-10ms of operation. Pi capacitors are used to filter out induction spikes, and I would not be surprised to see them on the breakout board already.

powering the arduino with a 12v 250mA source

Would reccomend against this. The arduino itself uses 45mA of current, which isn't a problem. What will be though, is the motors, which have to run on 205mA total. I would reccomend a 20A or higher suppply to properly power a decent motor, and an extra 5A for each motor thereafter.

\$\endgroup\$
  • \$\begingroup\$ Arduino says on their site though that 9v-12v is recommended, and the motors i am using operate at 3v - 7v, current is confusing me here. How exactly should I power it then? \$\endgroup\$ – Don Grey Aug 8 '16 at 15:04
  • \$\begingroup\$ well, you need not take only the voltage into consideration, but both the voltage and the current. The arduino will be fine, But I suspect that the motors will not be. Iwould suggest a current source that is rated for higher than 250mA. is this battery or line driven? \$\endgroup\$ – user86234 Aug 8 '16 at 15:09
  • \$\begingroup\$ motors are powered by battery \$\endgroup\$ – Don Grey Aug 8 '16 at 15:47
  • \$\begingroup\$ @Kr4t0s are you sure that the battery isn't 250mAh, not 250mA? \$\endgroup\$ – user86234 Aug 8 '16 at 15:47
  • \$\begingroup\$ Since its on a robot I just want one source that can decrease for the motors and remain the same for the arduino \$\endgroup\$ – Don Grey Aug 8 '16 at 15:47
0
\$\begingroup\$

I see a ground loop as L1 and L2 are daisy chained as opposed to a "star" configuration. Any DC current spikes in the DC- to L2 can have unwanted effects in L1 (and vice versa).

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.