Low-Power Asynchronous Solar Sensor

An asynchronous solar sensor, comprising:

• a pixel matrix comprising N rows and M columns of pixels, a common row line, a common column line and a plurality of comparators connected to the common row line and to the common column line
• wherein each pixel comprises a photodiode, working in the photovoltaic region, which comprises an anode and generates a voltage when illuminated, and wherein the comparators are connected to the anode of each photodiode and are configured to determine whether the voltage generated in each photodiode is greater than a threshold voltage,
• a pull-up transistor, connected to the common row line and to the common column line, configured for maintaining them at a high logic level and for transitioning to a low logic level when the voltage of at least one photodiode of the corresponding row or column exceeds the threshold voltage of the comparator connected to said photodiode,
• a pin-hole optics module, comprising a hole through which an external light passes and configured to generate with said external light an illuminated region on the matrix, and
• a processing module, connected to the common row line and to the common column line, and comprising:
• one or more memories, connected between the common row line and the common column line, and configured to store a signal from the common row line and the common column line of coordinates of the illuminated pixels which exceed the threshold voltage, and
• filtering blocks, connected to the memories, and comprising an input, for receiving coordinates of the illuminated pixels which exceed the threshold voltage, and an output, for outputting coordinates of a pixel positioned in a centroid of the illuminated region.