| 摘要 |
Oversampled Delta-Sigma modulator, including a first loop comprising a Delta-Sigma modulator for shaping the second-order quantisation noise to be quantified (31) with one bit and a second loop comprising a Delta-Sigma modulator for shaping the first-order or second-order noise to be quantified (38) with one bit for shaping the first- or second-order noise, characterised in that the input of the quantiser (31) of the first loop (25 to 31 and 34) also constitutes the input of the second loop (35 to 38 and 44), and in that it includes a digital gain stage (c) (43) arranged in series at the output of the second loop, the value of the gain (c) being calculated on the basis of the values of the gains (ki) and (kj) of the amplifier stages (26) and (29) of the first loop so as to optimise the spectral shaping of the quantisation noise, the gains (ki) and (kj) being chosen so as to optimise the voltage excursions and the dynamic range for a given power supply voltage and a given electronic noise level. <IMAGE>
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