A 1-GHz logic circuit family with sense amplifiers

This paper describes a newly developed logic circuit family based on dual-rail bit lines and sense amplifiers that is used extensively in a 1.0-GHz, single-issue, 64-bit PowerPC integer processor, gigahertz unit test site (guTS). The family consists of an incrementor, a count-leading-zero, a rotator, and a read-only memory. Each macro consists of a leaf-cell array, dual-rail bit lines, a row of sense amplifiers, a control block, and peripheral circuits. A common read-out scheme sensing the differential voltage of dual-rail bit lines is used. The hardware was fabricated in a 0.25-μm drawn channel length, six-metal-layer (Al) CMOS technology (1.8-V nominal VDD). Wafer testing was performed using a probe card. The macros were tested cycle by cycle by scanning the input data to the read/write address latches and data latches, and scanning the result out from the output receiving latches. Functional testing was performed on guTS macros at frequencies up to 1.0 GHz at 25°C with nominal VDD (1.1 GHz for the ROM)