A self-powered 2-dimensional motion detection chip

We demonstrate a self-powered chip to detect motion which enables constant, non-invasive monitoring. The chip was implemented in a standard 0.18 μm CMOS process. A P-N junction photodiode array was fabricated in the chip to detect when light is blocked by the movement of a hand or finger. The interface circuit detects the change between the shadowing and the exposure to determine the specific movement. This entire chip operates without any off-chip power supply and provides digitized outputs including 1 bit direction output and an 8 bits output indicative of the velocity in two dimensions.