Low-power system-on-chip acoustic localizer

We present the design of system-on-chip acoustic localizer chip that can be directly integrated with miniature MEMS microphone array. Continuous-time bandpass filtering and amplification at interface with microphone array enable low-power and small-form factor implementation. Time delays between acoustic signals observed over a planar geometry of four microphones are obtained by relating spatial and temporal differentials and estimated through mixed-signal least-square digital adaptation. Designed 3 mm × 3 mm chip in 0.5 μm CMOS technology operates with estimated 150 μW power dissipation at 16 kHz sampling rate.