A Low-Power Optical Receiver for Contact-free Programming and 3D Localization of Autonomous Microsystems

Optical receivers for autonomous microsystems provide benefits such as enabling contact-free optical programming and low-power 3D optical localization. A small, low power optical receiver is presented for transferring program data to a micro-controller's SRAM and detecting optical pulses from a lighthouse localization system. An integrated photodiode is combined with an inverter-based amplifier design to generate a digital waveform from optical input. A pulse width modulation scheme is used to allow clock and data recovery (CDR) to operate without any on-chip clock source. The receiver is able to achieve a data rate of 320 kbps for active and standby powers of 1.52 µW and 640 nW, respectively, while occupying 16,900 µm2. This optical receiver can also operate as a lighthouse localization receiver, enabling a completely integrated, low power method of localization for a monolithic integrated system. The successful programming of a lighthouse localization routine onto a monolithic integrated system is demonstrated. Using a commercially available HTC Vive V1 lighthouse base station, this optical receiver was able to provide relative azimuth and elevation data with RMS error of 0.386 degrees and 0.312 degrees, respectively, while consuming only 1 mW of power.