While designing an LM2586 SMPS circuit using the TI Workbench, the software recommended the following transformer:

SMPS Transformer

This is apparently the 749196510.

The TI workbench states that this is a 89.1uH part. However, the datasheet states that the inductance base is 9.9uH. Even if I were to connect all 3 primary windings in series, surely that would only result in 29.7uH? Is there a mistake somewhere?

  • \$\begingroup\$ Looks like a f$%^ up on the part of TI \$\endgroup\$
    – Andy aka
    Nov 2 '15 at 15:25
  • 1
    \$\begingroup\$ @Andyaka But they've done it on more than one part. I tried changing the parameters of the power supply and it chose a different inductor. Same problem: it said it was a 47.7uH part, but the datasheet said the base inductance is 5.3uH. \$\endgroup\$
    – Amr Bekhit
    Nov 2 '15 at 15:27
  • \$\begingroup\$ I think you should let the software decide on values but you do the part selection. \$\endgroup\$
    – Andy aka
    Nov 2 '15 at 15:29

Inductance goes as turns squared, so all three primary windings in series would get you 89.1uH.


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