This is Circuit DC to DC Converter. For input DC12V-24V 4A to Output 24V-48V 2A (inputX2) Use easy circuit simple part IC Digital Cmos : 40106 and Mosfet BUZ11 If you have power supply source about 12V, from battery 4A sizes. But want to enhance voltage be 24V or about 2 times. This circuit has can to help you by it has prominent easy good point. It use the integrated circuit digital number CD4093 perform produce the frequency drive current change CD40106 bilateral the group trips work. By drive high current with power mosfet BUZ11 make output current collect at capacitors the very total up voltage bilateral the group then is double of Input power supply. or It can enhance voltage double , be 2 times there. Detail to See Circuit.