A 131-dBSPL AOP 66.3-dB SNR 105.7-$\mu$ A-Standby All-Dynamic Digital Microphone with Self-Clocked Interference-Resilient Acoustic Activity Detection

This paper presents a 103.3dB-dynamic-range all-dynamic digital CMOS-MEMS microphone with internal acoustic activity detection (AAD). A voltage-boosting dynamic analog front end (VB-DAFE) is proposed to allow linear scaling of supply current with operating frequency and extend dynamic range (DR) under 1.8 V system supply. Besides, an event driven (ED) zoom analog-to-digital converter (zoom-ADC) is proposed to handle large output swing from the VB-DAFE. The VB DAFE and zoom-ADC allow the system to operate in an all dynamic manner, enabling scalable power with operating frequency, suitable for ED operations. Under a 1.8 V supply, this work achieves an acoustic overload point (AOP) of 131 dBSPL, a signal-to-noise (SNR) of 66.3 dB and a standby current of $105.7 \mu ~\mathrm{A}$ with internal self-clocked interference resilient AAD.