Simple 110 - 240 VAC to 2 x 30 VDC 50 - 100W SMPS .... where do I start??

[Baldin]

Hi All

New in this forum
I'm looking into building/constructing a small and simple 2 x 30 VDC SMPS for a small class-d amplifier.

Where would I start this?
What is a nice, easy, cheap controler to use?
Guess that a flyback converter with two output windings is the way to go
http://schmidt-walter.fbe.fhdarmstad...pw_smps_e.html

Would I need a PFC at the input? ... guess not.

Thanks in advance

[luka]

Hi

Well for that kind of power flyback would the best, it is small and simple.For drivers you can use something like SG or UC, or you can get something like VIPER from ST, TOPSwitch (see this )....

You don't need one, but some of this chips do have it anyway

[IVX]

Originally posted by luka
Hi

Well for that kind of power flyback would the best, it is small and simple.For drivers you can use something like SG or UC, or you can get something like VIPER from ST, TOPSwitch (see this )....

You don't need one, but some of this chips do have it anyway

I agree, TOPSwitch, or STR**** (Sanken) etc if no plan for big series of the device, otherwise one of the cheapest way uc3842+stp4n60=$.8

[Baldin]

Thanks Luka and IVX

uc3842 seems like a good choice. Just took a look at the data sheet. The coil "NC" ... any idea what it's for at how to calculate the value? ..... NC normaly means No Connection

[luka]

Hi

In thi case NC means Not Calculated. It is winding on trafo, used to supply (Vaux) chip after start-up, and depends of how much turns you put on primary.