increased the need for lowpower, high dynamic range (DR) audio ADCs. In these applications, the DR specification determines the maximum distance at which a low-cost microphone can obtain a good quality recording. THD+N (SNDR) is not as important as it is limited by the microphone performance. CTDSMs are chosen for audio applications due to inherent anti-aliasing and resistive input. This work presents a high-performance audio CTDSM designed in a 130nm process. The ADC achieves a DR of 118.5dB A-weighted (116.3dB un-weighted) over 20Hz-20kHz bandwidth while consuming only 3.3mW. Figure 9.5.1 shows the modulator, which consists of a 4th-order CIFF-B loop filter, OSR of 64, OBG of 2.25 and a 33-level quantizer. An 8-tap FIR filter desensitizes the feedback
DAC, Non-Overlap DEM and Continuous-Time Quantizer
Anand Subramanian, Tanmay Halder, Laxmi Vivek Tripurari, Anand Kannan Texas Instruments, Bangalore, India Applications requiring far field voice/audio recording have