200 MHz 0.8 μm CMOS gradient vector processor for real-time execution

This paper describes a gradient vector processor which forms an important part of a shading processor being developed for a high resolution high performance real-time general purpose volume imaging system. The proposed architecture overcomes current image resolution and frame-rate limitations through the use of custom high-speed processors. The gradient vector processor evaluates three arithmetic operations: a square and add operation, square-root, and three division operations. Fully pipelined operation produces a vector every 5 ns or with a 200 MHz frequency at V_dd=3 V and with an accuracy of ±0.78%. The algorithms and implementation in silicon are described in detail