Low-power circuit techniques for size-configurable SRAM macrocells with wide range of operating frequency are presented. Synchronous specification is employed to drastically reduce the power dissipation for low-frequency applications. Dynamic circuits applied to bitliness and sense circuits contribute to the reduction of power dissipation. To enhance the high-end limitation of operating frequency, a latch-type fast sense circuit and an accurate activation-timing control technique for size-configurable memory macrocells are proposed, and a special CMOS-level input buffer is devised to enable the minimum cycle time of fast synchronous memory macrocells to be evaluated with conventional LSI-test systems. A memory macrocell using these techniques was fabricated with 0.5-µm CMOS technology. Its power consumption strongly depends on the operating frequency, and at 3-MHz suitable for codeless telephone applications is less than 5% that of an asynchronous SRAM designed with full-static CMOS circuits. Its maximum operating frequency at 3.3-V in 100-MHz.