Embedded Design Handbook

ID 683689
Date 8/28/2023
Public
Document Table of Contents

3.5.3.5. External SRAM Types

There are several types of SRAM devices. The following types are the most popular:

  • Asynchronous SRAM—This is the slowest type of SRAM because it is not dependent on a clock.
  • Synchronous SRAM (SSRAM)—Synchronous SRAM operates synchronously to a clock. It is faster than asynchronous SRAM but also more expensive.
  • Pseudo-SRAM—Pseudo-SRAM (PSRAM) is a type of dynamic RAM (DRAM) which has an SSRAM interface.
  • ZBT SRAM—ZBT (zero bus turnaround) SRAM can switch from read to write transactions with zero turnaround cycles, making it very low latency. ZBT SRAM typically requires a special controller to take advantage of its low latency features.