An Embedded 32b Microprocessor Core for Low-Power and High-Performance Applications

An embedded RISC microprocessor core fabricated in a six-layer metal 0.18m CMOS process implementing the ARMTM V.5TE instruction set is described. The core described is the first implementation of the Intel XScale MicroarchitectureTM. (ARM is a registered trademark of Advanced RISC Machines, Ltd.) The microprocessor core, which includes caches, memory management units, and a bus controller, comprises a hard-embedded block 16.77 mm in size. The implementation is primarily custom logic in a variety of circuit styles. The processor dissipates 450 mW at 1.3 V, 600 MHz, and scales between 55 mW at 0.7 V, 200 MHz, and 900 mW at 1.65 V, 800 MHz. Architectural performance is 1000 MIPS at 800 MHz with efficiency ranging from over 850 MIPS/W at 1.65 V to over 4500 MIPS/W at 0.75 V. Architectural and circuit design approaches for low power and high performance are described and measured results from the initial implementation are shown. The first implementation VLSI chip has a 3.3-V pin interface and supports a 0.75–1.65-V core voltage range.