Dram with staggered word line transitions for hybrid-bonded photosensor arrays

Abstract

An image sensor has multiple blocks each with multiple pixels; each block uses a separate analog-to-digital converter (ADC). The ADCs feed digitized images into an image DRAM, and the image DRAM feeds digitized images to an alignment buffer in turn providing images to an image processor. The ADCs feed digitized image data into the image DRAM in hyperlong words, using staggered, overlapping, word lines to write each hyperlong word. A method of imaging includes exposing a photosensor array to light, reading pixels of the array in sequence within each block of pixels, one pixel in each block simultaneously; and digitizing pixels in separate ADCs for each block. Digitized pixels are written to image DRAM as hyperlong words with one pixel from each block in parallel using staggered, overlapping, word lines. Pixels are read from the image DRAM into an alignment buffer and thence to the image processor.