Truncation Error Compensation Technique with Auxiliary Noise Shaping Filter in CT DSM

This paper presents a truncation error compensation technique with auxiliary noise shaping filter in continuous-time (CT) delta-sigma modulator (DSM) with digital truncation. The truncation error compensation filter is used to reduce the quantization noise with low latency in feedback loop. An auxiliary noise shaping filter is proposed to suppress the truncation error leakage due to the mismatch between digital and analog filter. A CT DSM with proposed techniques achieves a SNDR of 75.7 dB and a DR of 78 dB with 25 MHz bandwidth.