Linear Power Supply

[Umma]

i designed a linear power supply whose cover 0-30V and 0-5A
Please send any diagram
Thanks

 

[ronv]

Just a few questions to get started.
Are you sure you want linear and not switching?
Do you need 5 amps at all voltages? This will make power dissipation very high at low voltage.
Linear regulators cannot go to 0 volts. Would 2 or 3 volts be okay for the lowest setting.
Would say 2 volts to say 20 volts be ok? Then an off the shelf regulator could be used.

 

[crutschow]

Linear regulators cannot go to 0 volts.

You can always design a linear regulator to go to 0V, and some you can buy do that. It's just that the most commonly used (the LM317) can only go down to 1.2V without additional circuitry.

 

[Sceadwian]

At 0 volts (or close to it) the regulator is going to have to dissipate 150 watts of power... A simple buck switch mode supply before the linear regulator can help this dramatically. But if you can't tell by the odd English that the user said they designed a 0-30V 5amp linear supply but they want us to supply the diagrams that something might be wrong with the original posters intentions...

 

[ronv]

Low voltage

Right you are. I was thinking about the other end.

0 volts, no problem.

 

[Umma]

thanks to all for answering

Are you sure you want linear and not switching?

I am not knowing SMPS supply
i design linear supply using lm317 but problem is that this regulator max 1.5A
please help me if i design SMPS supply

Do you need 5 amps at all voltages? This will make power dissipation very high at low voltage.

yes because for learnig

 

[Umma]

any body help me

 

[crutschow]

yes because for learnig

So this is just a paper design for school?

 

[Umma]

So this is just a paper design for school?

No
i making a power supply for home appcations and for learning electronics

 

[ronv]

Pre regulator

Can anyone offer some input on this as a pre=regulator for Ummas power supply. The objective is to reduce the power in the linear regulator at low voltages. Anyone have another real simple one?

 

[Umma]

hello ronv

 

[chemelec]

You might check out the Super Power Supply on my Projects page.
Not so Simple, But it will do what you want.

 

[ronv]

Power Supply

Umma,

Where are you located? What parts and skill level do you have?

Ron

 

[Umma]

Where are you located?

Pakistan

What parts and skill level do you have?

i design power supply using three pin regulator
1. lm317 the problem is that the current provide 400mA-1.5A at different voltage
2. lm338 the problem is that the current provide 1A-5A at different voltage
3. ua723 the problem is that the 7-30V
i design power supply 0-30V and 0-5A
using transistors and op amp

thanks ronv

 

[Damo666]

Hi Umma. If you're new to electronics i think you're doing right building a linear supply. I for one prefer linear power supplies as opposed to the switch mode variants. I power some real expensive radio gear on my psu, and have heard too many horror stories about smps units and their problems. You're also dealing with much safer voltages with a linear supply. Good luck.

 

[ronv]

Power supply

Hi Umma,

I have another friend, Hamid, in Chiniot, Pakistan. Small world.
I would like to have a nice supply myself, so maybe we can both build the same one.
I am not the best circuit designer, but as we go along we can have people here review the design. I would suggest that we work off line by e-mail then post once in a while if that is ok with you. We can also build in stages. 1- Transformer, bridge, and filter. 2- Basic voltage regulator. 3- Current limit. 4- High current (more transistors). Let me know by e-mail if this is ok. Ronv@wbhsi.net

 

[Umma]

sended mail

 

[ronv]

Bulk Supply

Hi Umma,

I didn't get your e-mail. Maybe you could post yours or try again.
Attached is the first step for our supply. The transformer is pretty expensive ($75 US). We can look around for a cheaper one. The parts datasheets can be seen on this web site: Electronic Components & Supplies
Let me know what you think so far.

Ron V.

 

[Umma]

I Send e-mail this address Ronv@wbhsi.net
my e-mail address siliconvalley2007@gmail.com
i see diagram that you send lm3852 why use



what is the value of capacitor (formula) that min out put ripple

 

[Umma]

I Send e-mail this address Ronv@wbhsi.net
please check and tell me now that mail receive or not