[Solved] L293D Motor Driver Shield

Not sure what is confusing you, as pictured it appears to be 6V so between 4.5 and 36 and if 2 x 18650 would be 7.4V so again between 4.5 and 36.

@zander Thanks. Also, this is a transistor based driver. And it needs 5V to run. Does a mosfet based driver like the vnh2sp30 needs a certain voltage to run? I`m looking on the datasheet and I see just the voltage for the motors. So it doesn`t need a dedicated power supply to run like the L293D/N?

Posted by: @cosmin676

Hi,

I would really appreciate it if someone could clarify some things with this motor driver.

I cant really understand the powering of it. I`ve read that it takes 5V to power any circuits and 4.5V-36V to power the motors. However the picture below says otherwise.

I`m confused because I see a lot of people power this with 2 18650 Li-ion 3.7v batteries.

Thanks.

Hi @cosmin676, To help answer this question, I've included this link which is for your shield board :

https://microcontrollerslab.com/arduino-l293d-motor-driver-shield-tutorial/

This tutorial will explain all the connects, power requirement, and how to connect to the MPU you are using.

let us know if you have more questions..

kind regards,

LouisR

@inst-tech Thanks a lot. I`m gonna close this thread because I think I got the idea from your article.

Also I found that a mosfet based driver also needs a 5v power supply to power the board.

@cosmin676 Sorry, I just assumed the board will have a voltage regulator on it to convert the input voltage to 5V for the transistor although the low value of 4.5 implies a buck/boost. Looking at the picture I don't see the traditional VR type chip but this does appear to be a very old style driver so I am not sure.

Is there a reason for this driver vs the L298N for instance or the TB6612FNG which has many benefits over the traditional L298N. Bill has videos about both.

@zander Indeed a mosfet based driver like the TB6612FNG is way more efficient.

So my conclusion is that around 5V is needed to run the driver in both case (L293D / TB6612FNG).

Another question. Lets take the TB6621FNG that outputs 2.5-13.5V (or at least this is what I found the voltage to be according to some datasheets). Will any motor that runs on a current in that range work?

And also will it work with no problems? I`m looking for an optimal solutions because I want my build to last.

For example, if I supply 12V for a motor that runs on 12V will be right and if the motor runs on 6V the 12V supply will cause the motor to break. Is this right?

And like you said, I`m not using any regulators or any buck/boost converters. Yet.

@cosmin676 My comment re buck/boost was to do with what is on the board. I can't see them but they are there as @inst-tech pointed out, there is a jumper to control the power supply for the logic. I do not own any of these boards or motors so take my answer with a grain of salt, if a motor runs on 6V why would you connect 12V?

@cosmin676, Indeed, running motor at higher voltages can, and does shorten their life expectancy and the internal resistance of a DC motor is fairly fixed, so increasing the voltage increases the current, and subsequently, the power dissipated by the motor in the form of heat. Power (watts) = V X I .

 IMHO, You should never operate a motor with higher than specified voltage and current. That much is true for most things in the electrical/electronics world..

With AC motors, it even more complex because of the inductive reactance (XL) which change the total resistance ( impedance) of the motor with respect to frequency the voltage and current is at.

As you can see, there is much to learn about this subject.. but, I'm sure you will do just fine..just remember, when you let the "magic smoke out", try to find out why, and try not to repeat it!...lol

happy project building, and be safe!

regards,

LouisR

Although I defer to the more hardware oriented guys here, the board you're showing is connected to stepper motors.  Depending on what kind of motors you're using, NEMA-17's  are happiest using 12 to 24V and actually run better at their higher end.  For future reference, I would suggest just using the little 3D printer drivers that are dirt cheap since they make a butt-load of them.  They run cool and include the aluminum fins to keep them healthy.  Bill has a video showing how to use them also.  

$1.49 per motor. 

"https://www.amazon.com/gp/product/B092Q4LZV7/"

https://www.amazon.com/gp/product/B092Q4LZV7/

Thanks a lot to all of you for your answers! I`ll have all this in mind!