PSRAM is called Pseudo Static Random Access Memory,which is pseudo static random access memory.It adopts DRAM's 1T1C(one transistor plus one capacitor)process architecture,but it realizes the ease of interface similar to SRAM.Compared with the 6T architecture of traditional SRAM,spi psram can provide higher storage density and more competitive unit cost under the same chip area.
 

The difference between PSRAM,SRAM and DRAM

①SRAM:extremely fast and low in delay,but limited in integration and high in unit cost.

②DRAM:High density and low cost,but it needs external controller to refresh regularly to maintain data.

③PSRAM:It has both the convenience of SRAM interface and the high density advantage of DRAM.
 

Introduction of high-density spi psram memory expansion scheme

The VTI164LA16LM represented by Yingshang is a high-density and low-power spi psram memory expansion scheme.It is a typical pseudo static random access memory.Although its internal architecture is similar to SDRAM,its external interface is extremely simplified.This spi psram model realizes the Self-Refresh function by integrating the refresh circuit into the chip,and can maintain data integrity independently without relying on an external controller.
 

Main specifications of spi psram memory chip VTI164LA16LM

①spi psram capacity:64Mb(organization mode:4M×16)

②Working voltage:1.7V~1.95V

③Access speed:two speed classes of 60ns/70ns are supported.

④spi psram package form:48BGA