Help regardig ""switch mode power supply of 24 volt 3.75 amps 90 watts""

[Kashif_932]

Help regardig ""switch mode power supply of 24 volt 3.75 amps 90 watts""

Hi to All,

I want to design SWITCH MODE POWER SUPPLY OF 24 VOLT 3.75 AMPS 90 WATTS and i don't want to use any controller in this project. actually it's analog based SMPS. i am using SG3525 PWM IC to generate PWM.

Can any one tell me which bridge rectifier should i use in my project?? transformer of what rating should i use??

i have also attached block diagram of my project .


i would be highly grateful to you people if you guide me in this project.


best regards;

 

[smijesh]

Re: Help regardig ""switch mode power supply of 24 volt 3.75 amps 90 watts""

SG3525 is a PWM IC and also a voltage mode controller.
It has frequency limitation (Up to 50KHz)
Preferably for push pull and bridge configuration.
Input AC voltage not mentioned? It will make a decision of bridge rectifier.
For 90W power E30 or EFD 30( @50KHz) transformer have to use and number of turns will depends up on primary voltage.

 

[Kashif_932]

Re: Help regardig ""switch mode power supply of 24 volt 3.75 amps 90 watts""

thanks sir for help,
actually i want to select bridge rectifier on the basis of input AC voltage 220v and frequency 50 Hz

- - - Updated - - -

Sir i have read the data sheet of SG3525 . you have said that limitation frequency is 50 KHz for this ic but in data sheet Oscillator Frequency Range is 0 to 400 KHz.

is Oscillator Frequency is something else ?? Kindly make it clear to me

thanks;

 

[smijesh]

Re: Help regardig ""switch mode power supply of 24 volt 3.75 amps 90 watts""

You can use 1A bridge rectifier for this circuit.
Let me check about 50KHz
Reffer this link

https://tahmidmc.blogspot.in/2013/01/using-sg3525-pwm-controller-explanation.html

 

[Kashif_932]

Re: Help regardig ""switch mode power supply of 24 volt 3.75 amps 90 watts""

Sir this ic "SG3525" isn't availabe in PROTEUS library... how can i have it in Proteus?
if you have .DSN file of this ic kindly send it to me..

thanks;

 

[schmitt trigger]

Re: Help regardig ""switch mode power supply of 24 volt 3.75 amps 90 watts""

At he power level you are planning, your best topology would be a forward converter. A flyback could also work, although not as efficiently.

Either way, the SG3525 is not a suitable IC for those topologies. An UC3842/3843 is a far better option. It is also inexpensive and widely available.

The following circuit is a typical flyback implementation:
https://obrazki.elektroda.pl/62_1236270596.jpg

Also please note that your block diagram does not include primary to secondary feedback insulation. It is a must if you are operating from a 220V line.

 

[Kashif_932]

Re: Help regardig ""switch mode power supply of 24 volt 3.75 amps 90 watts""

Sir how i can have these IC's in PROTEUS?? I MEAN SG3525 AND UC3842 are not available in PROTEUS SOFTWARE. because firstly i want to implement my circuit in PROTEUS then i would design it's PCB based circuit

kindly suggest me what i should do now?

 

[schmitt trigger]

Re: Help regardig ""switch mode power supply of 24 volt 3.75 amps 90 watts""

I am unfamiliar with Proteus. I use LTspice.

But I'm sure that there are specialized Proteus forums which can provide you with lots of good information and models. LTspice does have a very useful forum.

 

[FvM]

Re: Help regardig ""switch mode power supply of 24 volt 3.75 amps 90 watts""

Manufacturer SPICE models can be used with Proteus. The Proteus VSM help describes how to attach a SPICE model to a component symbol.

But I also don't use Proteus for circuit simulation an can't help ypu with the details.

 

[Kashif_932]

Re: Help regardig ""switch mode power supply of 24 volt 3.75 amps 90 watts""

i am using 1A BRIDGE RECTIFIER IC to convert 220v AC INTO DC.. can any tell me which formula will be used for this conversion? and at output what would be DC?


thanks

- - - Updated - - -

what is the difference bwtween SWITCH MODE POWER SUPPLY AND LINEAR POWER SUPPLY??

&

Difference b/w REGULATED and UNREGULATED POWER SUPPLY??


these terms are confusing for me.. kindly make them clear to me


regards;

 

[neddie]

Re: Help regardig ""switch mode power supply of 24 volt 3.75 amps 90 watts""

I found this file on some foreign(For me that is :0) ) site.
I make no claim about the validity if the models in here , but it may have what you want.
I can't read the language , so I'm not ever sure if there are any disclaimers etc. Hope not :0)

I do have a model for the 3842 ic in LTSpice , but have not tried Proteus.
cheers
Neddie

 

[Kashif_932]

Re: Help regardig ""switch mode power supply of 24 volt 3.75 amps 90 watts""

thanks a lot sir ... it's really what i was looking for..