LM5118: LM5118 -Power

Hello switch,

For 350W, you need 4 switches instead of 2 switches and 2 diodes. So in general I think even LM5175 or LM5176 gets to its limits at this power. Nevertheless, a 300W reference design is done on the EVM layout, see here: https://www.ti.com/tool/PMP10214

In general, I think LM5176 would be the right device for this appliction. Possibly this will work without external driver.

LM5118 has the limitation that it does not have pure boost mode and as in buck-boost mode both switches switch at the same time, if you just add 2 complementary drivers, 2 switches would be on at the same time when in buck-boost mode. I expect that this would work, but it is possibly not the best solution for such a high power.

Best regards,
Brigitte

Hi Brigittte，

Whether TI has this external Mos driver？

Hello switch,

Let me move the request to the MOSFET driver team. I am sorry, but I do not know these devices.

Best regards,
Brigitte

Hi Brigitte,

I encountered a problem when debugging LM5118, Vin=48V-62V, Vout=48V5A, MOS will break down. There is no problem with voltage input less than VIN=48V Vout=48V5A. Below is the circuit diagram 

Hi Brigitte，

Supplement: 

The LM5118 buck-boost regulator operates as a conventional buck regulator with emulated current mode control while VIN is greater than VOUT and the buck mode duty cycle is more than 75%.Is there a problem with working like this for a long time ？

Hi Switch,

i would like to review your schematic but many part descriptor are not readable as they are covering each other.
May you can also provide the details for the Transformer.

~ Stefan

Hi Stefan,

FYI,Thanks!

8713.Sheet1.pdf

Hi Switch,

thanks for the pdf - can you also share the transformer type or spec. Esp. RMS and saturation currents.

Thanks,

 Stefan

Hi Stefan，

Thanks，As attached