TPS40170: Using Buck converter in parallel.

Mason Noh

Expert 2490 points

Part Number: TPS40170
Other Parts Discussed in Thread: LM25119, LM5143-Q1, LM5140-Q1

Hi TI,

Kindly suggest me the best suitable dc-dc converter.

Requirement

Input: 12V

Output: 11V/ 50Amax

I couldn't find suitable converter.

So, Can I use TPS40170 in parallel? I'm wondering about OCP, SCP.

And maximum output current of LM25119 is 40A, If I use with external gate driver, Can it be up to 50A?

over 5 years ago

0 Timothy Hegarty over 5 years ago

TI__Guru 57412 points

Hello Mason,

Paralleling voltage-mode controllers is sometimes a challenge, so I recommend a two-phase solution for such a high current level. The LM25119 is worth looking at as its output current capabilitiiy is effectively dictated by the chosen FETs and inductor. However, it's Toff-min is quite high, so it is not suitable for low dropout applications, particularly at high switching frequency. One more appealing option is the LM5143-Q1 - here is the link to the EVM:

store.ti.com/LM5143-Q1EVM-2100-Dual-channel-automotive-synchronous-buck-controller-evaluation-module-P57612.aspx

It's Toff-min is 60ns, so it is suitable for low dropout. The product folder will be online in the next day or two.

Regards,

Tim

0 Mason Noh over 5 years ago in reply to Timothy Hegarty

Expert 2490 points

Hello
I couldn't find the product folder of LM5143-Q1.
Isn't it released?
And I don't need automotive rating. It has non automotive rating??

0 Mason Noh over 5 years ago in reply to Timothy Hegarty

Expert 2490 points

Thank you for your support.
If I change input voltage from 12V to 48V, Could you recommend suitable device??

0 Timothy Hegarty over 5 years ago in reply to Mason Noh

TI__Guru 57412 points

Hi Mason,

The LM5143-Q1 EVM is available in the estore and the product folder should be online later this week. This controller is also suitable for a 48V input. The LM5143-Q1 is very similar to the LM5140-Q1, but it has multi-phase capability and other updates (dither, resistor programmable Fsw, etc.)

Regards,
Tim

0 Mason Noh over 5 years ago in reply to Timothy Hegarty

Expert 2490 points

Hello

My design requirement is changed.

Vin: 12V, Vout: 9V, Iout: 70A

And I have tried to simulate design using TI webench tool.

But it was not able to create a design because of current limit.

But maximum output current is 100A in the product folder of LM5143-Q1.

Pleas let me know which spec is right?

0 Timothy Hegarty over 5 years ago in reply to Mason Noh

TI__Guru 57412 points

Hi Mason,

100A is possible with 4 phases. I think WEBENCH is setup for 2 phases maximum right now, but you can take that design and replicate by two. Also, please available of the LM5143-Q1 quickstart calculator available by download from the product folder. You can select 3 or 4 phases as needed (2 controller ICs) and design you circuit for 70A.

Regards,
Tim

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TPS40170: Using Buck converter in parallel.