48V power supply

[gelecg]

Hi,
I need a 48V power supply with 50 watt power(50W).the main voltage is 220V (rms).
can you help me with schematic?

the ripple is not important, larger than 10 volt with 50 hz frequency.

 

[MikeMl]

Why are you shouting?

It is all about finding a suitable transformer. Are you buying that? Where?

 

[gelecg]

ahhhh,
I know MikeMI.
The cost of power supply is important for me.
50 wat transformer is expencive.
I think the very easy flyback is better. the feedback is not important because the ripple is not important for me.
but a short current protection is need.
I think a flyback with self oscillation is very cheap.
So
Is there any schematic for help me?

 

[tcmtech]

Here is a 56 VA 36 volt dual primary transformer for $15.71.

Triad Magnetics - FD7-36 - Transformers - Power Products - Allied Electronics

When rectified it will give you around 60 volts open circuit but being a split wound transformer the primary and secondary windings are side by side which means that the secondary can be easily opened up and a few turns removed to drop the voltage down if necessary.

You wont get close to that price building your own SMPS.

 

[gelecg]

what about switching?
a flyback or halfbridge with self oscillation and thyroid core is very cheap, I guess.