The L4C381 is a flexible, high speed, cascadable 16-bit Arithmetic and Logic Unit. It combines four 381-type 4-bit ALUs, a look-ahead carry generator, and miscellaneous interface logic -- all in a single 68-pin package. While containing new features to support high speed pipelined architectures and single 16-bit bus configurations, the L4C381 retains full performance and functional compatibility with the bipolar '381 designs.