Off the shelf Transformer selection for Flyback DC/DC converter

[Mr.Cool]

i am wondering how to select an off the shelf transformer so it will meet my DC/DC converter needs.

let's say the only information i have is this transformer datasheet by Wurth Elektronik part number 750813134. This is a flyback transformer so i assume it is gapped and has "large" inductance which is good. its just an example, the one i think most likely to succeed, but if you have other off-the-shelf transformer better suited please let me know.
https://katalog.we-online.de/ctm/datasheet/750813134.pdf

i plan to use TOPswitch device to control converter so i don't care if is in continuous or discontinuous mode as the control chip takes care of the needs.

application specs:
Vin: 60V to 180V
Vout: 12V
Power: 12W
switching frequency: 132kHz (per topswitch datasheet)

when i follow Topswitch proceedure for converter design the equations are all geared towards finding the parameters you need so you can design your own transformer. but i dont want to design my own, i feel that there are a lot of transformers out there off the shelf, perhaps one is suitable for me?

my feeling is that the answer has to do with volt-second product and avoiding saturation of primary side inductance.

any help?

 

[BradtheRad]

Since I'm the kind who likes to experiment with simulations, I made one using your specs.

Your transformer ratio can be 8:1.
Although a flyback is normally designed for a 50% duty cycle, you have some leeway to make adjustments.



The primary needs to be a certain Henry value, so that it admits sufficient current during the first half of the cycle (132 kHz).

When you apply a 60V supply, you are drawing pulses of 429 mA, at a 64% duty cycle.

When the supply is 180V, you can draw slightly fewer mA, at a shorter duty cycle.

Notice your output capacitor must carry current bursts of several A.

My schematic has a few resistors which are there so the simulator won't make convergence errors. They are unnecessary in a real circuit.

 

[Mr.Cool]

thx Brad. matches my own thinking.

 

[schmitt trigger]

It appears that the transformer you've selected has merit for the proposed application.

At one of point of time, you will have to build a physical board and validate the design. I would watch for core temperature rise, and review the waveforms (specially the primary current) to ensure that it does not saturate under boundary conditions.