In the figure we have an application of an oscillator 4013 as voltage multiplier. It consists of a doubler capable of providing positive (a) or negative (b) output voltages. Entering with 5 V will have a 10 V output. The diodes are commonly used as 1N4148 or equivalent. The maximum output current is of the order of a few hundred microampers, which should be taken into account in practical applications. We take as base the 4093 integrated circuit, but nothing prevents that any CMOS inverter can be used in this circuit.
