A CHARGE-PUMP CIRCUITRY AND A METHOD FOR HIGH VOLTAGE GENERATION WITH IMPROVED PSRR

The present invention relates to a high voltage generating circuitry and a method to operate a high voltage generating circuitry. A charge-pump is configured to generate a high voltage based on a supply voltage and to provide the high voltage at its output. The circuitry comprises a control loop. A voltage divider receives at its input the high voltage and provides at its output a divided high voltage. A first circuit element provides a first voltage difference signal generated on basis of a comparison between a first reference voltage and the divided high voltage. A controller generates a feedback signal on basis of the first voltage difference signal. A voltage- or current-controlled oscillator generates clock signals for operating the charge-pump circuitry. Frequency of the clock signals generated by the oscillator is controlled with a control signal. The control loop further comprises a feedforward path with a second circuit element that combines a second reference voltage and a second voltage generated by inverting the supply voltage for obtaining a second voltage difference signal. A third circuit element generates, on basis of the second voltage difference signal, a feedforward compensation signal that is inversely proportional to a voltage difference between the supply voltage and the second reference voltage. A fourth circuit element generates the control signal by summing the feedback signal and the feedforward compensation signal.