US Patent 7113021 Voltage doubler circuit

The invention relates to a voltage processing unit comprising an integrated charge pump 11 for multiplying a voltage Vx applied to an input of the integrated charge pump 11 by a predetermined factor Xm. In order to enable a multiplication of an available voltage by a desired factor with a reduced required area for the integrated charge pump, it is proposed that the voltage processing unit further comprises an external voltage doubling circuit 12 for amplifying an available voltage Vdd and for applying the amplified voltage Vx to the input of the integrated charge pump 11. The invention relates equally to a corresponding method.