The Large Synoptic Survey Telescope (LSST) camera is supposed to be the largest digital camera ever constructed. Its size of 1.6 meters by 3 meters is roughly equal to that of a small car and it will weigh 2800 kilograms. It is a large-aperture, wide-field optical (0.3-1 μm) imager with image surface diameter of approximately 64 cm. The detector format will be a mosaic of 189 16MP CCDs providing a total of approximately 3.2 Gpixels. Each CCD has 16 outputs and is based on 10um pixel. The frame rate is 0.5fps, giving it a speed of 1.6GP/s.
LSST compiled a comparison of large cameras today:
Unfortunately, the schedule of LSST camera is quite long, the camera is supposed to be ready in 2020. I doubt it will be the largest by that time:
Actually, the recently constructed 0.5m x 1m 1GPixel Gaia camera is even larger in area, but lower in resolution.