SRAMs Race Along At Speeds Up To 333 MHz

Increasing the bandwidth of routers and switches, the 18- and 36-Mb Quad Data Rate II (QDRII) SRAMs are built on a 0.13 µm CMOS process and achieve speeds of 250 MHz for two-word burst and 333MHz for four-word burst devices. Deployed as buffer memory, the SRAMs provide bandwidths up to 1.33 GB/s. They provide two data ports that operate independently at double data rates, allowing the devices to output four data words per clock cycle. To minimize timing problems at all operating speeds, the data-valid window is set at 65% of the clock cycle. Available in x8, x9, x18, and x36 configurations with various speed ratings, the new SRAMs operate from a 1.8V supply and employ HSTL I/Os. Depending on the SRAM, sample prices range from $184 to $210. For more details, call Akiko Ishiyama at RENESAS TECHNOLOGY AMERICA INC., San Jose, CA. (408) 382-7407.