Selecting appropriate DRAM for MP257

[DMårt]

Hi!

I'm looking for an appropriate DRAM for the MP257.

I know there is a table about validated DRAM for MPUs.

https://wiki.st.com/stm32mpu/wiki/Validated_DRAM_on_STM32_MPU_portfolio

My question is if there is a DRAM standard i csn follow if I want to try another vendor of DRAM?

I'm looking for other types of DRAM that shares the same footprint and connection. But I'm unsure if it's good enough to select a DRAM on those specifications.

I've heard that there is a standard called JEDEC. If another vendor follows that standard, does that mean that this DRAM is compatible with the MP257?

For example: The MP257-DK is validated with MT53E1G32D2FW-046 WT:C, but that DRAM is out of stock. Could I use MT53E1G32D2FW-046 WT:B instead? It's the design B version instead of design C version.

[PatrickF · Accepted solution]

Hi @DMårt 

The major thing to look for is that it should be a single rank memory.
For LPDDR4 (i.e. single CS per channel), it is not always clear inside memory datasheets.

For DDR3L or DDR4 (should be single rank as well), it is simpler, and all JEDEC x16 with frequency above respectively 1066 and 1200 MHz should  work. 
See also Guidelines for DDR configuration on STM32MP2 MPUs

Looking at the references you mention, the revision B (Z42M) is NOT single rank (look at CS1_A and CS1_B)

While the revision C (Z42N) is single rank. So ok for STM32MP2.

Regards.

[DMårt]

Hi @PatrickF 

Thank you! Can you upload the datasheet of the C-revision of the Micron LPDDR4 memory?

I can't find it.

I want to compare if it's fits this Kingston Memory: B3221PM3BDGUI-U Kingston | Mouser Europe

It seems like Kingston is copying Micron.

Edit:

Found the revision C here.

https://www.aliexpress.com/item/1005009146059053.html