| 摘要 |
An audio amplification device includes an input for receiving an input audio signal and an output for delivering an output audio signal and an amplifier (OA 1 ) comprising a differential pair of MOS transistors. The gate of the first transistor is coupled to the input of the device. The gate of the second MOS transistor receives a reference voltage which takes the form of a rising ramp when the power is turned on. The drain of one of the transistors is coupled to the output. The amplifier also includes a biasing circuitry for biasing the bulk of the transistors to a first voltage level approximately equal to a supply voltage at the beginning of the reference voltage ramp, and to a second voltage level (V<SUB>BB</SUB>) approximately equal to the voltage of their source at the end of the ramp. The generation of a pop is thus avoided when the power is turned on, while still benefiting from an optimum PSRR in the normal operation phase.
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