Patent ID: 6774709
Filing Date: 2004-08-10
Classification: H02M,Y02B

Abstract:
A circuit for regulating an output voltage of a charge pump, the circuit comprising:a regulator connected to an output of the charge pump and comprising a voltage divider for dividing the output voltage, a comparator having a first input for receiving a divided output voltage, a second input for receiving a reference voltage, and an output for providing a digital signal, an integrating circuit connected to the output of said comparator for providing a control signal based upon an inverted digital signal, and a low-pass filter having a first input, for receiving the divided output voltage, a second input for receiving the control signal from said integrating circuit, and an output for providing a filtered divided output voltage, said low-pass filter having a time constant that is switched between at least two values as a function of the control signal, said comparator having a third input connected to the output of said low-pass filter so that the digital signal is based upon the divided output signal, the reference voltage and the filtered divided output voltage; a logic control circuit having a first input for receiving a clock signal, a second input for receiving the digital signal from said comparator, and an output for providing a timing signal for the charge pump; and a phase generator circuit having an input for receiving the timing signal from said logic control circuit, and an output for providing control phases for the charge pump.