WEBENCH® Tools/LM5122: Obtaining more power from LM5122 48V Boost

Prodigy 120 points

Replies: 11

Views: 243

Part Number: LM5122

Tool/software: WEBENCH® Design Tools

Looking to design 12V - 48V Boost converter using the LM5122MH/NOPB. The current needs to be 20A max but I get error from Webench stating current exceeds limit. Is there a way around this in simulation so I can get the design I need? I specified my range of input voltages between 20V and 30V. I am planning to run two 350W electric motors using this boost converter. Thanks.

11 Replies

  • Hi Amar,

    Thanks for reporting this, we're able to reproduce this and working on fixing it. We will keep you posted on the proceedings.

    Regards,

    Vishwanath

  • In reply to Vishwanath Tigadi:

    Hi Amar,

    This is a high current design. Single FET solution may not be sufficient for these input/output conditions. We're working on implementing parallel FET and Ideal Fet solutions. These changes may take till mid December for them to be released on ti.com

    Rergards,

    Vishwanath

  • In reply to Vishwanath Tigadi:

    .

  • In reply to Amar Brar:

    I made a mistake in my first question. For the 48V boost the input voltages are 20V - 30V and output voltage is 48V at 20A

    For 24V Boost, input voltages are 10V - 20V and output voltage is 24V at 40A.

    My sincerest apologies.

    Thanks

  • In reply to Amar Brar:

    Hi Amar,

    We're still working on this.

    Regards,

    Vishwanath

  • In reply to Vishwanath Tigadi:

    Hi Amar,

    Thanks for your patience. We will let you know once the Ideal and Parallel FET support for LM5122 is enabled.

    Best Regards,

    Harish

    _____________________________________________________________________________________________________

    If above reply answers your question please click on "This resolved my issue" button

  • In reply to Harish K R:

    No Problem. Will there be available a full board layout and bill of materials list in TI Webench because that is what I`m looking for. Will I be able to access before 12/15? I need this soon.

    Also, how many layers will the board be?

    Thanks

  • In reply to Amar Brar:

    Hi Amar,

    We are working to provide WEBENCH design support for high output power / load for LM5122.

    Kindly note that we might end up with either Ideal/Custom FET in case WEBENCH is unable to find suitable parallel FETs.

    Below is the current status for your conditions

    1. Vin=20V - 30V, Vout=48V at 20A

    We are able to get parallel FET for this design. Also inductor is resulting in custom component since high current rating inductors are not present in WEBENCH database.

    2. Vin=10V - 20V, Vout=24V at 40A

    Currently the device max Iout is limited to 35A in WEBENCH. So we are checking with product expert if this limit can be increased.

    Even if we enable high Iout design, we will most likely end up with Ideal FET for this design. Also inductor is resulting in custom component 

    Regarding PCB/Board, currently WEBENCH infrastructure doesn't support for Ideal/Parallel FET.

    Any changes that we do will mostly be available on ti.com by 20Dec2019. Kindly let me know in case of any queries.

    Thanks & Regards,

    Harish

    _____________________________________________________________________________________________________

    If above reply answers your question please click on "This resolved my issue" button

  • In reply to Harish K R:

    For the 24V Boost, I would be fine with max output current of 35A if I would be able to export the board design to altium. 

    If an inductor is custom can it be replaced by a through-hole footprint where I can install my own custom inductor?

    Thank you for the update,

    Regards,

  • In reply to Amar Brar:

    Hi Amar,

    For custom inductors and Ideal FET, you can download Altium files from WEBENCH and use inductor from local library.

    Thanks & Regards,

    Harish

    _____________________________________________________________________________________________________

    If above reply answers your question please click on "This resolved my issue" button