| 摘要 |
A sigma-delta analogue/digital converter stabilized by chopping (ADC) comprises a time-discrete multiplier for receiving an analogue input signal and a first time-discrete sequence, and for multiplying them so as to obtain a chopped analogue signal. A chopping-type sigma-delta ADC is connected in series to the time-discrete multiplier so as to receive and to convert the chopped analogue signal into a digital output signal, the chopping-type sigma-delta ADC being characterised in the z domain by: <IMAGE> where ST'(z) is a transfer function of the signal, and is characterised by a passband in the high-frequency range; and NT'(z) is a noise transfer function, and characterised by high attenuation in the high-frequency range. The low-frequency noise of the circuit may thus be suppressed in order to increase the resolution of the converter. <IMAGE>
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