Patent ID: 7961047

Claim:
An amplifier comprising: at least one switch controlled by an output voltage of a hysteresis block, and the hysteresis block, wherein the hysteresis block is adapted to receive a low threshold voltage, a high threshold voltage and an input voltage signal based on an integration of an error signal, the hysteresis block being arranged to change the output voltage of the hysteresis block 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 V ref −αV DD , and the high threshold voltage is equal to V ref +αV DD , where V ref is derived from a common mode voltage, α is a non-zero constant, and V DD is derived from a power supply voltage for the amplifier.