Patent ID: 7113021

Claim:
A voltage processing unit comprising an integrated charge pump for multiplying a voltage applied to an input of said integrated charge pump by a predetermined factor; and an external voltage doubling circuit for amplifying an available voltage and for applying said amplified voltage to said input of said integrated charge pump; said voltage doubling circuit comprising a capacitor, of which capacitor a first connection is connected to said input of said integrated charge pump; first switching means for connecting a voltage source to said input of said integrated charge pump when said first switching means is switched on; second switching means for connecting a second connection of said capacitor either to ground or to a voltage source; and control means for providing control signals which alternatingly switch on the one hand said first switching means on and second switching means to ground and on the other hand said switching means off and said second switching means to a voltage source; wherein said control means comprises a counter for switching said first switching means on and said second switching means to ground each time after having received a predetermined number of signals from said integrated charge pump in a startup phase, and a trigger circuit for switching said first switching means on and second switching means to ground with each signal received from said integrated charge pump in a subsequent regulation phase.