SDRAM Devices

The SDRAM devices used in the RAM expansion modules must be self-refresh type devices for operation from a 3.3-V power supply. The speed of the SDRAM devices must be 66 MHz or greater, corresponding to a cycle time of 15 ns or less.

Note

The computer may have 100-Mhz parts installed. This is normal, and does not indicate that the memory bus is running faster than the specified 66 MHz.

The devices are programmed to operate with a CAS latency of 2. At that CAS latency, the access time from the clock transition must be 7 ns or less. The burst length must be at least 4 and the minimum clock delay for back-to-back random column access cycles must be a latency of 1 clock cycle.