L298N overheating problem

Thread Starter

Bhatta55

Joined Jan 12, 2021
7
I am using a PWM input signal freq - around 500 Hz for driving a 12 V DC motor (less than 2 A). Input (PWM signal) is supplied at Enable "A" and IN 1 and IN 2 are either HI or LO alternately for FORWARD and REVERSE. The IC runs very hot even with heatsinks. Am I doing something wrong. Sometimes it heats up without the motor connected. I have checked all the connections and it is OK. Do you feel the frequency has something to do with it?
 

Alec_t

Joined Sep 17, 2013
12,149
Welcome to AAC!
The L298N is an IC which is used in various modules. Please upload a schematic of your set-up, and links to the specifications of any modules you are using. We're not psychic.
 

ideainnova

Joined Apr 19, 2013
5
I am using a PWM input signal freq - around 500 Hz for driving a 12 V DC motor (less than 2 A). Input (PWM signal) is supplied at Enable "A" and IN 1 and IN 2 are either HI or LO alternately for FORWARD and REVERSE. The IC runs very hot even with heatsinks. Am I doing something wrong. Sometimes it heats up without the motor connected. I have checked all the connections and it is OK. Do you feel the frequency has something to do with it?
Hello, i discarded all l293 series, old 80s level low efficiency control ic's above 100mA, and i even discarded electronics therefore too. You are right it is a stove rather than an ic. And there simply nothing in dip world. it is 2021 and we dont need to solder discrete parts if this is civilication of people. But it seems this is only productionside earth. Only some productspecific smd low current chips here and there. Try SparkFun Toshiba TB6612FNG. You will forget even what cooler is. Also xl4015 converter will give you 2.5-3A without any heat in the same efficiency. xl4005 also has enable pin but you can make 30hz max or it gets unnecessarily hot again over it. With 15V suitable safe transformer + xl4015 +lm138 current limiter + tb6612 + lcd arduino etc, you get an 2.5A lineer! type, power supply as tiny as a mandarin. If yuo have another highpower converter, you can mount toshiba tb6612s as paralel and you get more and more power, say 100A without heat. toshiba can switch very well at %50 duty at 80khz and goes much more loosing duty perfection.
 

Thread Starter

Bhatta55

Joined Jan 12, 2021
7
Hello, i discarded all l293 series, old 80s level low efficiency control ic's above 100mA, and i even discarded electronics therefore too. You are right it is a stove rather than an ic. And there simply nothing in dip world. it is 2021 and we dont need to solder discrete parts if this is civilication of people. But it seems this is only productionside earth. Only some productspecific smd low current chips here and there. Try SparkFun Toshiba TB6612FNG. You will forget even what cooler is. Also xl4015 converter will give you 2.5-3A without any heat in the same efficiency. xl4005 also has enable pin but you can make 30hz max or it gets unnecessarily hot again over it. With 15V suitable safe transformer + xl4015 +lm138 current limiter + tb6612 + lcd arduino etc, you get an 2.5A lineer! type, power supply as tiny as a mandarin. If yuo have another highpower converter, you can mount toshiba tb6612s as paralel and you get more and more power, say 100A without heat. toshiba can switch very well at %50 duty at 80khz and goes much more loosing duty perfection.
Thank you Ideainnova very much for your post and time . Really appreciate the advice and was at my wits end on solving this problem. I will take your advice and try the alternates suggested. Most definitely , I will post the result of my tryst with the new chipsets suggested.
 

Thread Starter

Bhatta55

Joined Jan 12, 2021
7
I second what @ideainnova says.
The days of the L298 are past.
For example, I've used an A4950 8 pin SOIC chip that has no heat sink other than the PCB and it runs rings around the old L298 chip.
40V and peak +/- 3.5A.
Not bad in a tiny package.
View attachment 241933
If you are interested, the data sheet is here..
https://www.allegromicro.com/en/Products/Motor-Drivers/Brush-DC-Motor-Drivers/A4950
(This PCB needs a clean!)
Thanks a ton. I liked your comment on the L298 acting as a stove.
 

Thread Starter

Bhatta55

Joined Jan 12, 2021
7
I second what @ideainnova says.
The days of the L298 are past.
For example, I've used an A4950 8 pin SOIC chip that has no heat sink other than the PCB and it runs rings around the old L298 chip.
40V and peak +/- 3.5A.
Not bad in a tiny package.
View attachment 241933
If you are interested, the data sheet is here..
https://www.allegromicro.com/en/Products/Motor-Drivers/Brush-DC-Motor-Drivers/A4950
(This PCB needs a clean!)
Thanks dendad . Really appreciate your help. Will get back on my experience of the suggested A4950 8 pin SOIC chip. Is it available in a pinout package instead of SMT as I use standard hobbyist PCB's available in the market.
 

dendad

Joined Feb 20, 2016
3,882
A4950 8 pin SOIC chip. Is it available in a pinout package instead of SMT as I use standard hobbyist PCB's available in the market.
No, it does not look like it.
But, there are other devices that you can use.
I don't know how these go..
https://www.ebay.com.au/itm/192154229161?hash=item2cbd48d9a9:g:l3kAAOSww3tY60zI
but you can always go bigger...
https://www.ebay.com.au/itm/324558079179?epid=1787320860&hash=item4b912b44cb:g:S~kAAOSw4pNgbGD4
In motor control, oversize is good!
 

Thread Starter

Bhatta55

Joined Jan 12, 2021
7
Thank you Ideainnova very much for your post and time . Really appreciate the advice and was at my wits end on solving this problem. I will take your advice and try the alternates suggested. Most definitely , I will post the result of my tryst with the new chipsets suggested.
This kit has a design to solder as paralel on top of other.
https://www.sparkfun.com/products/14451
Be careful on all advertised products. First of all, specs are at least 5x overrated on chips, simply too optimistic. Specs on top of first page are not valid alltime but are only individual extreme points(and in the special state mentioned at bottom of page 3856). Premade kit products are only for low current, only for amateur students, not for pro usage or never for maximum specs. Those coolers on them mean nothing, never enough for even midspecs. Kits dont have implementations necessary for safety and commonly dont suit t engineering guides well, easily pron to failure, yes cheap continuous marketing. Some pololu-like brands use realworld tests on their pages but up to a point. Common point is that noone mentions about efficiency openly, silly secret. No datasheet has efficiency graph. if you are lucky, you will see efficiency values measured by users only.
3:43
Be careful also that most of chinese kits use fake of western chips. They run but simply out of specs. Buy western chips from west(digikey etc directly). However some chinese products are also terrific. xl4015 is the one(with vertical coil, good labels, correct cap values). However, you cant get the same batch everytime because chinese distributors dont make any warranty on this. So just luck, yet cheap. Finally test your oem options and compare them in your own project's parametric environment to see final valid result (and in a closed real box where it will be).
 

Attachments

Thread Starter

Bhatta55

Joined Jan 12, 2021
7
I second what @ideainnova says.
The days of the L298 are past.
For example, I've used an A4950 8 pin SOIC chip that has no heat sink other than the PCB and it runs rings around the old L298 chip.
40V and peak +/- 3.5A.
Not bad in a tiny package.
View attachment 241933
If you are interested, the data sheet is here..
https://www.allegromicro.com/en/Products/Motor-Drivers/Brush-DC-Motor-Drivers/A4950
(This PCB needs a clean!)
Thank you dendad,

You seem to also be a fellow sufferer and have an awesome store of knowledge. I have ordered BT 57960 preassembled board from Amazon as it seems to be over the top as far as my current requirement is concerned (around 2.5 A with a sq. wave PWM signal of 0-18 V p-p). Will receive it on 28th June. I must really thank you for taking so much of your time to educate me.

Thank you.
 
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