In this paper, a high throughput fully hardwired CABAC encoder is proposed for real-time encoding video of ultra high resolution, e.g., QFHD (3840times2160). We analyze the distribution of bins in various syntax elements and accordingly propose a new architecture which includes an optimized context memory access scheme, a multi-bin binary arithmetic encoder (BAE), and an SE-specific cycle-reduction context modeler for increasing BAE utilization. Our architecture can process up to 8 bins per cycle. Running at 222 MHz, it is capable of real-time encoding QFHD video in the worst case of main profile level 5.1. We have successfully integrated the proposed CABAC encoder into an H.264/AVC encoder system using a multi-media SoC platform.