The objective of this project is the design of a low power circuit to localize a sound source in the audio range using a pair of microphones as illustrated in the figure.
Microphones setup to detect a sound source
The circuit is based on a neuromorphic cross-correlator and it can estimate the bearing angle of a sound source one mile away with one degree precision. Below you can see a picture of the 2mm by 2mm IC version (0.35µm). The chip has a total power consumption of 660uW, a total of 170.000 transistors and works with a 200Khz clock.
A 208 stages cross-correlator calculator
The following is the latest version of the correlator. This one has only 64 stages, but can be cascaded to other units giving more flexibility to the design. It is a 3mm by 1.5 mm design (0.5µm) and has a total current consumption of 20µA @ 3.3V.
64 stages correlator design