What is really meant by negative voltage?

[lyy1992]

Hi, I get confused when I look at the dual power supply. I wish I can add two capacitor bank at both +ve and -ve terminals to improve its regulations.

If I connect the capacitor bank, maybe 0.1F directly to the supply line, there must be a sudden high current flow through the rectifier (surge current) and will cause damage on it. So I decided to make something like protector to protect the circuit from surge current by charging up the capacitor bank first, then reconnect it to the supply line.

But when I saw the negative supply, I get confused. How to connect the protector circuit to the negative voltage?

Well, I think is like 2 batteries connected in series. Then I assumed that the center ground as the positive terminal of the lower part of the battery. If so, I can just copy the upper circuit of positive supply to the negative supply, isn't it? Can someone please check whether I connected the circuit correctly? Is the concept correct? Thanks.

[PLAIN]http://dl.dropbox.com/u/34919012/Untitled.jpg

 

[Vailanor]

Yes, your concept is correct and your circuit diagram looks good. You can use a diode bridge rectifier to protect the dual power supply from any surge current. This diode bridge will allow the capacitor bank to charge up gradually and then reconnect it to the supply line. Make sure to use a proper current rating for the diodes in the bridge rectifier to prevent any damage due to overcurrent.