摘要 |
A filter applied in a sigma-delta modulator includes an integrator, a signal attenuator and a feedback circuit, in which these components are connected in series sequentially to form a local feedback circuit. The integrator integrates an input signal to output an integral signal. Accordingly, the signal attenuator attenuates the integral signal to output an attenuation signal to the local feedback circuit so as to share a part of attenuation amount to reduce the chip area of the sigma-delta modulator.
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