TNY277 design with pi expert: Secondary inductance??

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Hi

I want to design a Flyback converter with a TinySwitch-III and the PI Expert Suite (Ver 10.1).
The basic parameters are:

Input: 85~265VAC 60Hz
Output: 12VDC, 1.2A (14.4W Simple output)

I read the aplicattion notes (AN-16~19, AN-23, and more) but i can not find anything (formula or explication) about the secondary inductance.
Therefore, in the PI Expert there is no "secondary inductance" parameter.

Really, I am not a professional power-supply designer but I think the secondary inductance is necesary to the construction of the transformer.

1) Can you show me the formula for the secondary inductance calculation?

Thanks

PD. Excuse me for my ugly english
Raul Diez.

Hello,
PIExpert provides primary inductance value. PI Expert also provides primary and secondary turns. The ratio L/(N^2) is constant. what that means is that Lp/(Np^2) is same as Ls/(Ns^2). From the primary inductance and primary number of turns you can compute Lp/(Np^2) and using the result, you can compute Ls or secondary inductance.
Regards,

Hello PI-Sarek,

Thank you very much for your help.

Regards.