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Topic: L298N Motor Driver Power (Read 213 times) previous topic - next topic

Ikram101

So I am using a L298N driver module and want to know something. I looked in the datasheet but couldn't find it; how many amps can I feed into it safely? The datasheet says it draws current in mA. What would happen if I connected it to a 2A power supply? Should I use a current limiting resistor? If I do, won't the motors get less amps? Do they get the same voltage? Sorry if I asked stupid and obvious questions. Help!

JoeNova

I feed mine the 12v power/ground straight from my car battery. Seems to be fine.

Ikram101

I have this battery lying around with no labels or specs. So I got out my multimeter. It shows a potential difference of 4.65V and sources ~1.6A when connected directly, sans driver, to 4 dc motors in parallel. So will that be safe to power two modules and thus control 4 motors?

jremington

The L298 is very old, very inefficient and works very poorly with a power supply of less than about 8V.

Pololu has much better motor drivers.

Ikram101

Ah I see. Thanks for the link. But can I use it in any way possible with what I have? It's a necessity. Please help

jremington

#5
Oct 12, 2017, 07:03 pm Last Edit: Oct 12, 2017, 07:07 pm by jremington
Quote
But can I use it in any way possible with what I have?
Only you can determine that.

Most of us would not even bother to try.

TomGeorge

#6
Oct 13, 2017, 10:18 am Last Edit: Oct 13, 2017, 10:20 am by TomGeorge
Hi,
If you look at the L298N datasheet.
It will tell you that a TOTAL of 4Amps.
BUT that comes with a fact that 2 amps per driver, and when conducting there is a typical 2V drop.
So 4W is being dissipated in HEAT in the chip, so it should have a heatsink on it.

The current that will be drawn through the IC will depend on the MOTORs you use, not the current rating of the power supply.





Tom... :)
Everything runs on smoke, let the smoke out, it stops running....

MarkT

So I am using a L298N driver module and want to know something. I looked in the datasheet but couldn't find it; how many amps can I feed into it safely? The datasheet says it draws current in mA. What would happen if I connected it to a 2A power supply? Should I use a current limiting resistor? If I do, won't the motors get less amps? Do they get the same voltage? Sorry if I asked stupid and obvious questions. Help!
The current used to power the chip is completely different to the current it passes to the motor.

The chip uses mA in its internal circuitry, but it can drive "upto 2A" per output.  Never a good idea to
take a chip to its limiting value though, 1A to 1.5A is a more reasonable expectation.  When the outputs
are off, the only current left is that powering the chip.

The current is determined by the load response to the voltage it gets - power too big a load from a
L298 and you'll fry the L298.  The power supply just has to have enough current in reserve to handle
the peaks of current demand.

Adding any sort of resistor in a power circuit is basically throwing away power as heat - avoid this
if possible.
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

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