3D In-Sensor Computing for Real-Time DVS Data Compression: 65nm Hardware-Algorithm Co-Design

Traditional IO links are insufficient to transport high volume of image sensor data, under stringent power and latency constraints. To address this, we demonstrate a low latency, low power in-sensor computing architecture to compress the data from a 3D-stacked dynamic vision sensor (DVS). In this design, we adopt a 4-bit autoencoder algorithm and implement it on an AI computing layer with in-memory computing (IMC) to enable real-time compression of DVS data. To support 3D integration, this architecture is optimized to handle the unique constraints, including footprint to match the size of the sensor array, low latency to manage the continuous data stream, and low-power consumption to avoid thermal issues. Our prototype chip in 65nm CMOS demonstrates the new concept of 3D in-sensor computing, achieving <6 mW power consumption at 1-10 MHz operating frequency, and >10× compression ratio on 256×256 DVS pixels.