MP2348GTL won't sustain 3A

DC-DC Power Converters
1

Hi,

currently working on DC/DC powersupply with 20~15V input and 10V 3A output.
According to specs 4A is the max DC current. But even with a 3A DC current this
will not sustain for more then 15 seconds.

Then what i assume thermal protection starts the hiccup mode and
no longer maintain the output voltage and current.

Design and PCB layout are based on the reference design.

Any ideas to improve this ?

Regards Rens

2

Hi Rens,

I will recommend to check the soldering first. And check whether the IC is broken. MP2348GTL can work normally below 150C, you can use a thermal camera to check the maximum working temperature. If you find the highest temperature exceeds 150C, you can use some physical methods to lower the temperature such as using electric fan or try to use heat sink on the IC.

However, I think it might not be the thermal issue. You can increase your inductance. If you still have questions, feel free to contact me. I am glad to help.

Sincerely,
Fox

3

Hi Rens,

Our typical application circuits show up to 20W, but your application is 30W. This may exceed the maximum continuous power dissipation that the device can tolerate.

Sincerely,
Fox

4

Hi Fox,

thank you for all your suggestions, reducing the power output to 20 W fixes the problem
and current and voltage remain stable. However the design request is 30W e.g 3A/10V.

Was thinking to use the MP2349GG instead, but this one has no availabillity at my distributer.
Is this the right choice for my application or can you recommend another part.

Regards Rens

5

Hi Rens,

Yes, you can use MP2349GG. I think it is good enough for your application.
With your current requirement, I will also recommend MP8759, but I don’t know whether you have other requirements. If MP8759 is good for you, I prefer MP8759. It has higher maximum power limit, which is safer.

Sincerely,
Fox

6

Hi Fox,

thanks you for the recommandation, I will upgrade my design and use the MP8759.

Regards

Rens

7

Hi Fox,

during the re-design i found out that the recommende operation range for Vout is
0.6 to 5.5V. This does not meet my requirement for a 10V output. Any other suggestions
on part to use.

Regards Rens

8

Hi Rens,

Try MP2386. I think it is good enough for your application.

Sincerely,
Fox