# building a power supplier

Discussion in 'General Electronics Chat' started by enid, Jun 6, 2010.

1. ### enid Thread Starter New Member

Jun 4, 2010
4
0
hi, how are you.

I am such a beginner in electronics so I'd be very grateful if someone can help me.
I have to build a simple power supply that work with an input of 220v AC and has an output of 1A and 12V DC. I have to build the circuit in two deferent ways:
1-with transistors
2- with LM723

thank you !

2. ### Bychon Member

Mar 12, 2010
469
41
So...what's the question?

3. ### enid Thread Starter New Member

Jun 4, 2010
4
0
can anyone help me building these circuits?

4. ### R!f@@ AAC Fanatic!

Apr 2, 2009
9,666
1,110
googling can find u lot's of circuits.
find one, post it, and then we can discuss it.
do ur home work first

5. ### enid Thread Starter New Member

Jun 4, 2010
4
0
i have google it but i did not find anything similiar.
anywhere , thank you !

6. ### R!f@@ AAC Fanatic!

Apr 2, 2009
9,666
1,110
U want a series regulator and an IC regulator.
try these for series regs

File size:
15.5 KB
Views:
25
• ###### Discrete-Voltage-Regulator1.gif
File size:
8.7 KB
Views:
27
enid likes this.
7. ### retched AAC Fanatic!

Dec 5, 2009
5,201
316
The first thing you need is a transformer to drop the line voltage to a safe level. And a level closer to your end result.

If you look at the datasheet for the LM723 you will find its input voltage range.

You need a transformer that will drop the voltage to about 2 volts above that number.

One of the reasons you want it a few volts higher, is you will be needing a bridge rectifier to convert the AC to DC.

Bridge rectifiers use diodes to do the work. As we all know, diodes will drop the voltage a certain amount. So, you have to be sure the starting voltage on the secondary of the transformer is high enough.

mahmoodsani likes this.

Apr 5, 2008
18,684
3,635
enid likes this.
9. ### enid Thread Starter New Member

Jun 4, 2010
4
0
thank you very much to everyone )

Mar 24, 2008
21,416
2,948
11. ### mahmoodsani Member

Jun 3, 2010
43
0
thanks v much for such brief explanation