LNK306 can used low inductance or not?

Posted by: maeman123@gmail.com on 06/19/2019

Hi,

I have design small supply for give power for switching controller ( SG3225, push pull transistor and transformer gatedrive) Half-bridge switching power supply converter for Audio amplifier.
By used LNK306 and used switching inductor 1mH (600mA Isat and coat with conformal coating chemecal ) but I have some small noise (air noise in inductor).
And this made trouble for me to much. becuase, this noise have amplifier to speaker.

I try to fix it with many method (vanish Inductor and glue together with PCB, etc. ) but it still have audio noise.
Then, I have to keep it wrong value of inductor (I need to increase it to 2.2mH) 220uH and put it in my power supply board.
I not have any audio noise out.

So, can I used this value 220uH of inductor for LNK306 in this design? *in this time I didn't install with amplifier circuit.

Thanks
Maeman ;)

Comments

update

Yesterday, I have try my power supply to main Audio amplifier.
And it didn't get noise out to speaker and audio noise from power supply board.

I not sure for this can be used like this or not (used 220uH for inductor switch coil).

Can some PI answer for something for it?

regard
Maeman

Please let us know if you require 220uH or 2200uH (which is 2.2mH).

Normally the audible noise goes down when the AC component of flux is reduced. If you can send me the details of both the inductors (core dimensions/type, number of turns, core material etc.) we can help answer your question.