The Godfather talking
This is god damn my place! Capisci?
Sonsivri
 
*
Welcome, Guest. Please login or register.
Did you miss your activation email?
December 08, 2016, 07:10:07 19:10


Login with username, password and session length


Pages: [1]
Print
Author Topic: 12v 220v Dc-Dc  (Read 2382 times)
0 Members and 1 Guest are viewing this topic.
gevv
V.I.P
Active Member
*****
Offline Offline

Posts: 146

Thank You
-Given: 44
-Receive: 500



WWW
« on: February 12, 2008, 07:13:27 19:13 »

used pc atx power transformer








Orjinal



easy circuit



Logged

Umarım gelmez ilham perilerimin sonu... ! Modifiye uzmanı web üzerinde 320volt.com ile yaktı mumu....
huanfai
Newbie
*
 Muted
Offline Offline

Posts: 8

Thank You
-Given: 1
-Receive: 1


« Reply #1 on: March 27, 2008, 05:28:21 17:28 »

I was like you... Tongue I've also made a same one but I blew my transistor because my heatsink is too small.........  Cry
I belive that your transistor is very hot when you operate it..... Embarrassed
You can improve your circuit by using a pwm controller to make the output being regulated so that can save a lot of power and protect your transistor being fried....
That is a pwm controller IC that is a free sample from Texas Instrument that match your need: MC33063A   Grin
« Last Edit: March 27, 2008, 05:41:15 17:41 by huanfai » Logged
picavr
Active Member
***
Offline Offline

Posts: 169

Thank You
-Given: 184
-Receive: 100


« Reply #2 on: January 06, 2009, 12:17:03 12:17 »

hi gevv ,can you give me more information about transformer fouund in atx power supply,because i have a project about an high voltage generator (variable) ,in the atx box there are generally 2 transformers,;what is the methode   
Logged
tAhm1D
Senior Member
****
Offline Offline

Posts: 336

Thank You
-Given: 103
-Receive: 180



« Reply #3 on: January 06, 2009, 08:38:13 20:38 »

Hi,
The above placed circuit by gevv is simple but it is good for only testing purpose. Simplicity is not always good in smps. The circuit is uncontrolled and risky as flyback circuit requires lot of transient suppression because in this circuit, peak current is 5.5 times than the nominal current and since no suppressor is used in this circuit, one should be very careful in testing this circuit.

For Picavr,
Yes, in normal ATX Power Supply, there are 2 transformers. One is main transformer, may be EI33 or ERL35 and another is Pulse Transformer, small in size, used to drive the gate of Mosfets or base of Transistors.
Logged
ajmain
Guest
« Reply #4 on: January 18, 2009, 01:41:56 13:41 »

gevv,
You can improve this circuit by adding a mosfet driver before the mosfet maybe by using a totem-pole stage or any ready-made IC. You should also add a snubber across the transformer primary and if possible from drain to ground. Plus, you should rectify the high frequency to dc before the lamp.
Logged
Jagi
Newbie
*
 Muted
Offline Offline

Posts: 17

Thank You
-Given: 12
-Receive: 3


« Reply #5 on: January 24, 2009, 03:58:49 15:58 »

Hi,
The above placed circuit by gevv is simple but it is good for only testing purpose. Simplicity is not always good in smps. The circuit is uncontrolled and risky as flyback circuit requires lot of transient suppression because in this circuit, peak current is 5.5 times than the nominal current and since no suppressor is used in this circuit, one should be very careful in testing this circuit.

tAhm1D I agree with your observation. The above circuit and the associated diagram is very good for someone who is learning about SMPS and how it operates. In the real world you'll need more than just a 555 IC.

@ gevv, how fast is the output switching? Remember the faster the output is switching the more the energy that is dissipated in the MOSFET driver. Additionally, one also needs to keep in mind the saturation of the core, which results in decreased efficiency of the SMPS as drive frequency increases.
Logged
Pages: [1]
Print
Jump to:  


DISCLAIMER
WE DONT HOST ANY ILLEGAL FILES ON THE SERVER
USE CONTACT US TO REPORT ILLEGAL FILES
ADMINISTRATORS CANNOT BE HELD RESPONSIBLE FOR USERS POSTS AND LINKS

... Copyright © 2003-2999 Sonsivri.to ...
Powered by SMF 1.1.18 | SMF © 2006-2009, Simple Machines LLC | HarzeM Dilber MC