A charge pump circuit and method for supplying power. The charge pump
circuit includes a first circuit receiving at least one low voltage
signal and generating an output voltage signal. The charge pump circuit
also includes a second circuit receiving a clock signal and the output
voltage signal. The second circuit sends a request signal based on a
comparison of the output voltage signal with two reference voltage
signals, where the two reference voltage signals are derived from two
supply voltage signals having a substantially constant potential
difference. The charge pump circuit further includes a high voltage
generator receiving the request signal and sending the two supply voltage
signals to the first circuit and the second circuit. The high voltage
generator adjusts the voltage potentials of the two supply voltage
signals such that the voltage potential of the output voltage signal
falls between the voltage potentials of the two reference voltage
signals.