need to make a dual supply from a single supply

[desperado1]

dual supply from single supply

I have a single power supply of 15V. I need a +15V, -15V and ground terminal from that very power supply to operate the operational amplifier. Is it possible to make from it or require another configuration ?

 

[Externet]

single supply to dual supply

Yes it is possible. Some questions first:
-How many accessible terminals are there in the power transformer secondary winding?
-What is the current capability of the existing power supply?
-What is the current consumption of the intended circuit?
-Is the operational amplifier to be fed with ±15 V or can work with ±5V ?
-Do you have a second identical power supply?

 

[VVV]

-ive supply from positive supply using 555

You can use a buck-boost regulator. As an example, the LM5118 from National.
Another example is the LT3483 from Linear Technology https://www.linear.com/pc/productDetail.jsp?navId=H0,C1,C1003,C1042,C1033,P8151

Or you can use a 555 a transistor and an iductor and build an inverting switcher, that produces say -18 to -20V. then use a linear regulator to bring that down to -15V.

 

[is_razi]

single supply dual supply

if you only need to supply a few opamps and you need currents up to 150mA there is a simple solution : ICL7660 , it can output -3... -12V related to its configuration using a positive input.here is the datasheet:
also you can use a 555 IC and some diodes and capacitors to build a negative supply using positive inputs. just google it (555 negative supply) to find bunch of schematic for it.

 

[desperado1]

555 negative supply

can u suggest me the simplest negative supply using 555 timer coz most of the schematics that i searched are a bit too complex for me.

 

[kanand078]

single to dual supply ic 15v

pls use the negative voltage generator

 

[is_razi]

+-5v sual supply schematic single positive

if you had searched the aforementioned keywords you must had found a bunch of sites for the problem. anyway here are some of the sites i found for negative supply using a 555 ic.in fact they are simple smps ,i am saying again that these are low current output supplies for cases like negative rail of a few opamps and etc:

http://freecircuitdiagram.com/2008/...-negative-supply-from-single-positive-supply/

**broken link removed**

http://www.csgnetwork.com/ne555c1.html


hope to solve your problem.