ac/dc converter power supply

[wwwkhunchan]

dc power supply in cambodia

Dear everybody,

I need schema of ac/dc power supply with 220 vac input and 5 vdc output without using any transformer.

I wait for your help and replies.
Thank,

khunchan

 

[IanP]

transformator less ac/dc converter

**broken link removed**
https://ww1.microchip.com/downloads/en/AppNotes/00954A.pdf
**broken link removed**

If you do search on GOOGLE you will find more ..

Regards,
IanP

 

[jsps]

ac/dc transformer-less power supply will be not having any isolation, will it work for you?

 

[nguyennam]

You did not mention about the current you need, as well as the purpose of using that converter.

In general, you will need a capacitor/power resistor to extract 5V from 220VAC, which component choosen, and how much is its value, depending on the current you need.
IanP already gave you the typical circuit using capacitor.

nguyennam

 

[alasliu]

hard to do it

 

[jsps]

why dont you build a bridge rectifier with 1n5408,then filter capacitor and then voltage divider with high wattage to get 5V. But if load somehow draws more current, it may be problematic, so there should be some overcurrent protection. and also think about isolation.

 

[saurav_sdpl]

U dont want a mains transformer, or no transformer.

Well if u dont want a mains transformer u could go for an SMPS.

Whereas if u dont want any transformer to be used , then PLZ specify the current rating of ur supply.

If it is less than 200mA then u can directly convert mains voltage to DC , use a voltage divider network to reduce the voltage, and then a DC-DC converter.

I hope this mite work for you

 

[wwwkhunchan]

Thank for ur all usefull advices. right now I can do it, because I need only a small current < 1A.

Regards,

Khunchan

 

[tillu]

i donot understand why you donot want any transformer in your supply. thing will be unnecessery lossy in that case. 1A is not a small current if above sugesstions are to be implemented.