please help: -24V output

[manju_bhat]

Hi All,

I have 19V AC coming out of transformer , which i am rectifying and generating +24V dc out put.

I wanted to have -24V at same time as another output ?

But -24V could be maximum of 1A load.

How to get -24v from +24V or present +19V AC ?
Is there any ready made module from any standard manufacture ?

please help..

thanks

 

[keith1200rs]

Half wave rectification would allow you to get both +24V and -24V at the same time.

Keith

 

[Takeshi-san]

1)Do you have just one coil, which gives 19V AC?
2)Can you use different transformer?
3)Do you need stabilize output?

 

[manju_bhat]

Hi,

thanks for reply,

Yes, I have only one coil. Transformer has only one secondary whcih is giviing me 19V AC . I can not change the transfomer . Already +24V is generated through rectification.

regulation is not necessary. Little variationis accepted on -24V line .

How to generate -24V @ 0.25A either by 19V Ac or +24V dc output ?

thanks.

 

[Takeshi-san]

use "voltage doubler", connect it to the secondary coil and stabilize output. It's ok for 250mA current

 

[manju_bhat]

Dear Takeshi-san,

thanks for your reply.

Would give me the ciruict that you have suggested? i dont not have idea..

please provide me that circuit , with all specified value of components . thanks

 

[Takeshi-san]

https://t2.gstatic.com/images?q=tbn:hRCp_5drmPMidM:

P.S. one of the first links in google "voltage doubler"

---------- Post added at 00:11 ---------- Previous post was at 00:09 ----------

https://t3.gstatic.com/images?q=tbn:OyVbRiPYDslMcM: one more diodes for your current, capacitors 1000mkF

 

[keith1200rs]

Or you could just use half wave rectification like I suggested a few days ago. I don't see what the purpose of a voltage doubler is when you actually request a negative and positive supply.

Keith.

 

[manju_bhat]

Dear All,

thank you very much.

Best regards
Manju