Low-power spiking chemical pixel sensor

An ISFET-based integrate and fire neuron, forming the front-end of a chemical pixel sensor, is introduced. With the sense data being encoded in the spike domain, i.e. asynchronous/continuous time and discrete value, it is directly compatible with asynchronous communication hardware, e.g. address event representation. The circuit is shown to be tunable to yield a linear relation with both pH and actual hydrogen ion concentration, with a peak power consumption of 35 mu W Furthermore, its compact pixel footprint of under 6500 mu m(2), makes it ideal for use in arrayed architectures with application in biochemical imaging.