Hello
I have a small project and i want to create a full wave rectifier. I drew the following circuit
But i am having a negative result

Can anyone help me?
The sine wave is :
DC = 0 V
AC = 16 V
VOFF = 0 V
VAMPL = 16 V
FREQ = 60 Hz

 

Can't see your images. If you are having problems, take a look at my blog entry here.

 

Post your (reasonably sized, like under 100KB) images as attachments to your post (use the Upload a File link at the bottom).

 

 

Are they clear now?

 

Of course you will get negative voltages. Turn your rectifiers around.

 

Post your (reasonably sized, like under 100KB) images as attachments to your post (use the Upload a File link at the bottom).

Are they clear now?

 

Of course you will get negative voltages. Turn your rectifiers around.

Thank you very much. I turned the rectifiers and the output turned out right. But when i added a resistor on the output i had the following result.
Any suggestions?

 

Then increase the value of C1 to 1000μF.

BTW, use a thread title better than Urgent!!

 

Then increase the value of C1 to 1000μF.

BTW, use a thread title better than Urgent!!

Thank you! I will use better titles.

 

What size resistor did you use? How can we give good feedback if you don't give us the information?

Since your output appears to be drooping from 14V down to 1V and that is being pulled from a 0.83uF cap, that means that you are pulling about 11uC of charge from it. Since that is being pulled out in 1/120th of a second, that's an average current of about 1.3mA. Since the average voltage is about 6.5V, I'm going to guess that you are using something like a 5kΩ resistor. Is that close?

If you follow how I did that, then see if you can work backwards to find a good capacitor value to use to keep the droop (also known as ripple) below a desired value.

 

What size resistor did you use? How can we give good feedback if you don't give us the information?

Since your output appears to be drooping from 14V down to 1V and that is being pulled from a 0.83uF cap, that means that you are pulling about 11uC of charge from it. Since that is being pulled out in 1/120th of a second, that's an average current of about 1.3mA. Since the average voltage is about 6.5V, I'm going to guess that you are using something like a 5kΩ resistor. Is that close?

If you follow how I did that, then see if you can work backwards to find a good capacitor value to use to keep the droop (also known as ripple) below a desired value.

Man you're a genius!

 

Man you're a genius!

Wouldn't go anywhere near that far, that's for sure. But thanks anyway.

What size resistor were you using?

Did that help you size your capacitor better?

What was the final result?

 

Wouldn't go anywhere near that far, that's for sure. But thanks anyway.

What size resistor were you using?

Did that help you size your capacitor better?

What was the final result?

I was u sing a 1K resistor. increasing the capacitor's size to 10mF made the result perfect.

 

I was u sing a 1K resistor. increasing the capacitor's size to 10mF made the result perfect.

Yeah, in increase by a factor of 10,000 probably reduced your ripple voltage for that size load down to a millivolt or two. It will give you a pretty high inrush current, though.

 

Please note that 1mF is 1000μF.

 

Please note that 1mF is 1000μF.

Yes. So an increase from 0.83uF to 10mF is an increase by a factor of over 12,000.