Parallel saturating multioperand adders significantly improve the performance of global system for mobile (GSM) speech coders by giving compilers and assembly language programmers the ability to parallelize loops containing saturating dot products, while maintaining GSM compliant results. This paper presents four designs for parallel saturating multioperand adders. These designs have at most one carry-propagate adder on their critical delay path, yet produce the same results that would be obtained if the additions were performed serially with saturation after each addition. The four parallel designs offer tradeoffs in terms of area, worst case delay, and dot product latency. Compared to a 5-input serial design, the 5-input parallel designs have delays up to 3.51 times shorter.

The desire for higher performance and higher resolution continuously increases the pixel update rates needed in high performance graphics systems. The increasing density of memory chips on the other hand reduces the pixel update rate that can be provided by the frame buffer. We present the design of a VLSI chip and a graphics system that can sustain sub-nanosecond pixel rendering rates for three-dimensional polygons and can be used to render about a million Z-Buffered and Gourard shaded polygons per second. The chip has been designed at the IBM Research Division's Thomas J. Watson Research Center.