Webench/LM5116: LM5116 Webench Simulation issue

Hi Keng Poh Kok,

The "Show Why Other Parts Were Not Found" option did not come up because the no solutions were available for these design requirements: Vin=90-100V, Vout=36V, Iout=3A, Ta=30degC.

If I reduce the output current to 2.5A, there are some solutions that show.  From there you can see the message for LM5116: WEBENCH can not find a suitable FET for this design.

Please let us know if you have any further questions.

hi Kelvin,

I don't understand, LM5116 datasheet spec it can run upto Iout<20A, why now only 3A also cannot simulate. So can this work on iout say 15A?

Best regards,

Kpk

Hi Keng Poh Kek,

Yes, the LM5116 may be able to support up 20A designs but it also depends on the duty cycle of the design and the output power. The maximum output current for this design that WEBENCH can provide will depend on a combination of the Vin and Vout requirements.

For the above test case you have at Vout=36V, a 20A design would result in an output power of 720W, far exceeding the power we can deliver from any FET currently in our database. The FETs you would typically use can only deliver so much power to the output before they overheat, and WEBENCH will create designs that ensures this does not happen.