An ultrasonic filterbank with spiking neurons

To support our ongoing work in modeling bat echolocation, a binaural, ultrasonic cochlea-like filter bank has been designed with moderate quality (Q) factor (as high as 65) with spiking neurons that are driven by the filter outputs. The neuron addresses are reported off chip at the time of the spike in an unarbitrated fashion and in current-mode to reduce the amount of capacitively-coupled feedback into the filters. This chip was fabricated in a commercially-available 0.5 μm CMOS process and consumes 0.425 milliwatts at 5 volts.