working with Step Down DC-DC Converter TPS54361

[Arpit Gupta]

I am now considering to design a power supply using TPS 54361
https://www.ti.com/lit/ds/symlink/tps54361.pdf

Using the spit rail supply, i will be creating positive and negative voltages,as given in
https://www.ti.com/lit/an/slva369a/slva369a.pdf

My question is , can i use a multi winding transformer instead of a coupled inductor in order to create mutliple power supplies??

 

[BrunoARG]

Almost every common transformer (50/60Hz) have a very low working frequency, because they are designed to work at those frequencies, and not both but one of them depending of the area line supply.

Inductors and switching transformers have much higher working frequencies because that helps to reduce the components size, cost and increase the efficiency. If you want to obtain different potentials, you should get a switching transformer (those yellow tape covered ones) or wind your own toroidal transformer by hand making the correct calculations for the frequency you're using.

 

[BradtheRad]

My question is , can i use a multi winding transformer instead of a coupled inductor in order to create mutliple power supplies??

If your loads are unchanging, then it is easier to succeed with a multi-winding transformer.

Reason: if you change the load at one winding, it can affect output voltage from other windings.

The TI article is about making a bipolar supply from a 2-winding inductor. If you can get equal volt output even with unbalanced loads, then that is clever.

 

[Arpit Gupta]

I am going to power the gate drivers of mosfets like the IR2110 and other sensor ICs through this multi-winding high frequency transformer ,
I believe then the current output of all the windings wont vary much in this case,will it work then???

 

[BradtheRad]

It is likely your flux field will build/collapse to different peak levels, depending on how heavy your chief load is.

If your chief load were to change, then that will cause different dynamics of the flux field. That is likely to affect the volt level coming from your auxiliary windings. (I'm not sure how much.)

Therefore it may be a good idea if you design the auxiliary windings to produce a much higher voltage than you need, to give you some headroom in case it drops. You'll also need to add couple volts, anyway, for regulating downward to your desired voltage.