Arduino shutting down

Hello, I have an arduino board mega 2560 and I used the arduino to control a servo with a joystick input.
I tried to disconnect the arduino from my computer and instead use a 11.1v LiPo battery to power up the arduino, I've connected the plus terminal to the Vin pin and the negative one to the GND.
At first, the arduino seemed to work fine but when I moved the joystick too much and to quickly, the servo moved fast and made the arduino board shutdown. This issue repeated it self many times and nothing seems to fix it.

However, when I've connected the arduino to the computer, the servo was able to move fast without making the arduino shutdown.
In case you're wondering, The C rating of the battery is very high(around 20) and it's capable of powering up this small servo without any problem.

Does anyone know what's causing this problem and how to fix it?
If so please let me know.

I suspect you are drawing power for the servo from the Arduino 5v pin and it is not able to supply enough current. Give the servo a separate power supply and make sure that the servo GND is connected to the Arduino GND. A pack of 3 x AA alkaline cells (4.5v) should be suitable for testing to see if my guess is correct,

The likely problem is that the Arduino's 5v regulator is overloaded when trying to step down from 11v to 5v. However, even when using USB power it is not a good idea to draw power for motors from the Arduino 5v pin - it may damage the PC rather than the Arduino.

...R

Robin2:
I suspect you are drawing power for the servo from the Arduino 5v pin and it is not able to supply enough current. Give the servo a separate power supply and make sure that the servo GND is connected to the Arduino GND. A pack of 3 x AA alkaline cells (4.5v) should be suitable for testing to see if my guess is correct,

The likely problem is that the Arduino's 5v regulator is overloaded when trying to step down from 11v to 5v. However, even when using USB power it is not a good idea to draw power for motors from the Arduino 5v pin - it may damage the PC rather than the Arduino.

...R

I indeed used the 5V pin from the Arduino to power up the servo, I didn't know that it's not good for the Arduino.
But anyway, I will try to do what you've suggested and connect the servo to an external power supply and the Ground pin to the Arduino GND, but how can I control the servo with the Arduino when it's not connected to the 5v Pin?
Could you explain the wiring of your suggested setup?

A normal servo has 3 wires. Positive (often red) to supply +ve, servo ground (often black) to Aduino ground and supply -ve. Then the signal wire (often white) goess to an Arduino digital pin to control it.

Steve

slipstick:
A normal servo has 3 wires. Positive (often red) to supply +ve, servo ground (often black) to Aduino ground and supply -ve. Then the signal wire (often white) goess to an Arduino digital pin to control it.

Steve

Robin2:
I suspect you are drawing power for the servo from the Arduino 5v pin and it is not able to supply enough current. Give the servo a separate power supply and make sure that the servo GND is connected to the Arduino GND. A pack of 3 x AA alkaline cells (4.5v) should be suitable for testing to see if my guess is correct,

The likely problem is that the Arduino's 5v regulator is overloaded when trying to step down from 11v to 5v. However, even when using USB power it is not a good idea to draw power for motors from the Arduino 5v pin - it may damage the PC rather than the Arduino.

...R

That's the setup I used:


I've connected the servo to the power supply instead as robin suggested.
Have I done something wrong or Is it correct?

Don't connect the Arduino 5v pin to the breadboard -only the GND

...R

Pretty useless picture. Can I assume the 4 x AA battery marked 5.6V is actually the 3S 11.1V Lipo you were talking about?

So according to that picture you have 11.1V connected directly to the servo. What servo do you have that is specified to run on 11.1V? I'm surprised the servo hasn't gone up in flames. Are you certain that's how it's connected?

Steve

slipstick:
Pretty useless picture. Can I assume the 4 x AA battery marked 5.6V is actually the 3S 11.1V Lipo you were talking about

So according to that picture you have 11.1V connected directly to the servo. What servo do you have that is specified to run on 11.1V I'm surprised the servo hasn't gone up in flames. Are you certain that's how it's connected

Steve

Hey Steve, The external power supply is indeed 4xAA batteries like it shown in the schematics, I followed robin's suggestion and used 5v power supply, although the voltage supplied by the batteries is 5.6v and not 4.5v as expected.

dindibo4:
I followed robin's suggestion and used 5v power supply, although the voltage supplied by the batteries is 5.6v and not 4.5v as expected.

I suggested using 3 x AA cells whereas you seem to have used 4. I don't think it will matter as most servos can work with 6v. But I definitely would NOT connect 5.6v to an Arduino.

...R

I'm really confused now. So what happened to the 11.1V Lipo?

Steve

slipstick:
I'm really confused now. So what happened to the 11.1V Lipo?

Steve

At first I used the 11.1v LiPo battery to power up the arduino by connecting the plus terminal to the Vin and the negative one to the GND pin, but the arduino still got shut down so then I tried Robin's suggestion with the AA batteries.

Robin2:
Don't connect the Arduino 5v pin to the breadboard -only the GND

...R

I've tried what you said and the servo didn't moved at all, I don't think I've understood the wiring.
Could you please explain how to connect the servo and the arduino?

This is what I have in mind.

dindibo4-serv0.jpg

...R

dindibo4-serv0.jpg

Not to knock any previous post from this n00b …

However, for clarity, both the UNO and the 2560 is capable of an input voltage ranging from 7-12 volts via the VIN pin per 2560 specs and UNO specs. On multiple occasions, I have used a 9v battery to power a 2560.

Robin2:
This is what I have in mind.

dindibo4-serv0.jpg

...R

Thank you very much, I've tried your setup and it worked.
Thanks for the help. :slight_smile:

dindibo4:
I indeed used the 5V pin from the Arduino to power up the servo, I didn't know that it's not good for the Arduino.
But anyway, I will try to do what you've suggested and connect the servo to an external power supply and the Ground pin to the Arduino GND, but how can I control the servo with the Arduino when it's not connected to the 5v Pin?
Could you explain the wiring of your suggested setup?

Every post practically on servos mentions this - if you'd search this forum a bit you might have spotted this.

Servos contain motors, motors take lots of current and put heavy interference on their supplys, so its good
practice to keep motor supplies separate from other, less robust, electronics such as logic circuitry.

Here the LiPo is plenty strong enough to power both the Arduino and the servo - I'd suggest using a cheap
LM2596 buck converter board (very cheap on eBay) to generate 6V for the servo, which will need probably
about 1A peak.

The Arduino on-board regulator cannot handle anything like that peak current, BTW.

MarkT:
I'd suggest using a cheap LM2596 buck converter board (very cheap on eBay) to generate 6V for the servo, which will need probably about 1A peak.

That sounds like a good idea.

I just suggested the 4.5v battery as a quick and convenient way of testing.

...R