POWER SUPPLY 12V - not with 7812

[iruraz]

POWER SUPPLY 12V

Hello,

Is there any schema for 12 volt power supply? (it doesn't content ic like 7812)

 

[pranam77]

POWER SUPPLY 12V

Do you require a regulated output? If yes what is the current requirement? regulated 12 volts can also be derived from feeding a 12.6 volt zener diode with 15 volts and utilising the same to feed a transisitor which will boost up the current. As a drop of 0.6 volts results in the transistor, 12 volts regulated will be available. Cheers

 

[iruraz]

Re: POWER SUPPLY 12V

Current is not important. I want to obtain 12V dc output. There is 220V 50 hz ac
input. And i can not use ic (like 7812) for regultaion as i said before.
Thanks for your help...

 

[pranam77]

POWER SUPPLY 12V

You may either use transformor or capacitor based power supply to drop the voltage to arround 15-18 volts and as you say the current is not important, you may use Resistor + zener diode combination to get 12 volts. Cheers

 

[hameeds01]

Re: POWER SUPPLY 12V

non isolated power supply as u mentioned above current is not important ok

 

[iruraz]

Re: POWER SUPPLY 12V

Hi again,
Isolation is important and i want to use transformer. Can you help me about transformer? How can i choose it?

Thanks for your help.
Regards.

 

[pranam77]

Re: POWER SUPPLY 12V

Hi again,
Isolation is important and i want to use transformer. Can you help me about transformer? How can i choose it? Thanks for your help. Regards.

If isolation is important, just use the same circuit given by Hameed, with 0-15 coil, but connect the bridge rectifier with the secondary of the transformor, and use a resistor 100E 0.5 watt in between the + and the Zener diode as shown in the figure below.. Cheers

 

[iruraz]

Re: POWER SUPPLY 12V

Thanks @pranam77.
Cheers.