In this paper we present an analogue integrated circuit containing a matched pair of silicon cochleae and an address event interface. Each section of the cochlea, modelled by a second-order low-pass filter, is followed by a simplified Inner Hair Cell circuit and a Spiking Neuron circuit. When the neuron spikes, an Address Event is generated on the asynchronous data bus. We present the results of the chip characterisation and the results of an Interaural Time Difference based sound localisation experiment using the AER EAR. The chip was fabricated in a 3-metal 2-poly 0.5μm CMOS process.