Many times we needed symmetric voltage, but we do not have the possibility him of taking immediately, from a existing supply. Then it will be supposed him we create from the existing single. This can become with the help of IC1. The output symmetric voltage has the half honour from simple. In the circuit the price of single voltage is + 6V until + 40V, in the output will take symmetric voltage ± 3V until ± 20V 3Amp. For example, if we supply the circuit with + 24V, then in the output we will have symmetric voltage ± 12V. The new point of report [ 0V ] him we have from the exit of IC1. Capacitors C1 and C2 should be placed much as possible, near in the IC1, the C3 and C4 should they are placed straight above in out pin of IC1. If the circuit is manufactured on printed circuit, should the wireways have enough heavy, because the current are possible to elapse in them is enough big [ 3Amp. ], the cables of connection it should they have also these certain good cross-section. The IC1 should be placed on a good heatsink.
circuit from http://users.otenet.gr/~athsam/symmetrical__from_single_voltage.htm