Abstract: A DC/DC converter comprising a first charge pump circuit including first MOS transistors including first depletion MOS transistors, an oscillating circuit connected to the charge pump circuit only at the gates of some at least of the first MOS transistors, including the first depletion MOS transistors.

Abstract: There is described a self oscillating modulator circuit comprising at least two coupled self oscillating loop modules, that achieved a good efficiency and a good linearity.

Abstract: A method generates a reference voltage by steps including: generating a reference signal from a voltage source; generating a comparison signal of the reference signal with a voltage reference; sampling the comparison signal; adjusting a numerical value as a function of the result of the comparison and of the numerical value; and converting the current numerical value into a voltage corresponding to the reference voltage.

Abstract: There is described a self oscillating modulator circuit comprising at least two coupled self oscillating loop modules, that achieved a good efficiency and a good linearity.

Abstract: A method generates a reference voltage by steps including: generating a reference signal from a voltage source; generating a comparison signal of the reference signal with a voltage reference; sampling the comparison signal; adjusting a numerical value as a function of the result of the comparison and of the numerical value; and converting the current numerical value into a voltage corresponding to the reference voltage.

Abstract: A method and corresponding circuit that adjusts the gain of an audio output stage having a class D amplifier, this method including the steps of setting the gain to a nominal value, analyzing an output signal during successive clock periods, counting the number of clock periods during which the signal is in a state corresponding to a saturation, decreasing the gain if the number reaches, before the end of a first time interval, a value corresponding to a first percentage, maintaining the gain constant if, at the end of a second time interval, different from the first interval, the number corresponds to a second percentage being comprised between the first percentage and a third percentage, and increasing the gain if, at the end of the second time interval, the number corresponds to a fourth percentage, lower than the third percentage.

Abstract: An amplifier having at least one switch controlled by an output voltage of a hysteresis block, wherein the hysteresis block is adapted to receive an input voltage signal based on an integration of an error signal, a low threshold voltage and a high threshold voltage, and is arranged to change the output voltage from a first value to a second value when the input voltage signal is higher than the high threshold voltage and to change the output voltage from the second value to the first value when the input voltage signal is lower than the low threshold voltage, and wherein the low threshold voltage is equal to Vref??VDD and the high threshold voltage is equal to Vref+?VDD, where Vref is a common mode voltage level, ? is a non-zero constant, and VDD is a power supply voltage.

Abstract: An amplifier having at least one switch controlled by an output voltage of a hysteresis block, wherein the hysteresis block is adapted to receive an input voltage signal based on an integration of an error signal, a low threshold voltage and a high threshold voltage, and is arranged to change the output voltage from a first value to a second value when the input voltage signal is higher than the high threshold voltage and to change the output voltage from the second value to the first value when the input voltage signal is lower than the low threshold voltage, and wherein the low threshold voltage is equal to Vref??VDD and the high threshold voltage is equal to Vref+?VDD, where Vref is a common mode voltage level, ? is a non-zero constant, and VDD is a power supply voltage.

Abstract: A method and corresponding circuit that adjusts the gain of an audio output stage having a class D amplifier, this method including the steps of setting the gain to a nominal value, analyzing an output signal during successive clock periods, counting the number of clock periods during which the signal is in a state corresponding to a saturation, decreasing the gain if the number reaches, before the end of a first time interval, a value corresponding to a first percentage, maintaining the gain constant if, at the end of a second time interval, different from the first interval, the number corresponds to a second percentage being comprised between the first percentage and a third percentage, and increasing the gain if, at the end of the second time interval, the number corresponds to a fourth percentage, lower than the third percentage.

Abstract: An amplifier having at least one switch controlled by an output voltage of a hysteresis block, wherein the hysteresis block is adapted to receive an input voltage signal based on an integration of an error signal, a low threshold voltage and a high threshold voltage, and is arranged to change the output voltage from a first value to a second value when the input voltage signal is higher than the high threshold voltage and to change the output voltage from the second value to the first value when the input voltage signal is lower than the low threshold voltage, and wherein the low threshold voltage is equal to Vref??VDD and the high threshold voltage is equal to Vref+?VDD, where Vref is a common mode voltage level, ? is a non-zero constant, and VDD is a power supply voltage.

Abstract: A digital/analog amplifier includes the following coupled in series: a pulse-width modulator, a control circuit, a power inverter and a filter. The power inverter comprises two transistors series-connected between a power supply terminal and a ground of the amplifier. The control circuit drives the transistors of the power inverter. One output of the filter forms an output of the amplifier to which a load is connected. The amplifier also comprises a capacitive circuit parallel-connected to the output of the power inverter.

Abstract: A digital/analog amplifier includes the following coupled in series: a pulse-width modulator, a control circuit, a power inverter and a filter. The power inverter comprises two transistors series-connected between a power supply terminal and a ground of the amplifier. The control circuit drives the transistors of the power inverter. One output of the filter forms an output of the amplifier to which a load is connected. The amplifier also comprises a capacitive circuit parallel-connected to the output of the power inverter.