STM32MP1 & STM32MP2 DRAM Recommendations (Supply Chain Crisis)

[alw]

Hi

I designed a PCB with an STM32MP157 using a Micron LPDDR3 memory. When I started the layout, I was advised that the memory would be available at least until 2029, so proceeded in good faith. When I came to order prototype samples back in March, I found that there was a Last Time Buy of August 31st this year.

The only option that I had was to change the layout to support DDR3L memory, however with the current DRAM supply crisis, I do not have confidence that this generation of device will have sufficient longevity of supply to justify the investment in mass production.

My alternative is to jump to an STM32MP2-based board and use DDR4 or LPDDR4 memory which will likely be available for longer but again with the current supply chain situation, these generations could also be obsoleted sooner than anticipated. I already read of DDR5 and LPDDR6 memories coming on stream.

Two questions:

With regard to the STM32MP1 and STM32MP2 processors, what is ST’s best guidance about which DRAM memory types to use please?

Is there any way of future-proofing STM32MP1 and STM32MP2 designs please by allowing the use of newer DRAM devices, such as 5th and 6th generation?

Kind regards,

Al

[Windows]

Hi ​@alw 

LPDDR4 is also going EOF. 

Micron and Samsung have announced that they are going to perform a last ship of LPDDR4.

For ST, this won't be any problem because they have a contract with Micron. But for us other, we need to seek other suppliers such as SK Hynix, Nanya Technology, Winbond and CXMT (ChangXin Memory).

My recommendations is to try out LPDDR4 from Aliexpress, Ebay etc. They are cheap, but takes time to get delivered. 

[David Littell]

Good luck with that - you’ll likely end up with counterfeit junk that will fail at one (or more) of the 4 corners.

[Windows]

Good luck with that - you’ll likely end up with counterfeit junk that will fail at one (or more) of the 4 corners.

Hi ​@David Littell 

I bought genuine Micron LPDDR4 from Aliexpress and they are working.

Samsung K4FBE3D4HM-TFCL 4GB LPDDR4 4266Mbps chip IC 200 ball RAM

https://a.aliexpress.com/_Ewwh08m

 

Micron: 

MT53E1G32D2FW-046 WT:B D8CJG MT53E1G32D2FW-046 WT:C D8DVT LPDDR4/4X 4GB 4266Mbps 200FBGA 32Gb Memory Chip IC Integrated Circuits

https://a.aliexpress.com/_EyudthG

When I did bought then, they cost 20 USD/each. Now they cost 160 USD/each.

[alw]

Thanks for the recommendations, I didn’t know about LPDDR4 being phased out quite so soon.

I’ve been burnt by the counterfeit silicon experience, so am only looking at mainstream distributors like Avnet rather than AliExpress, Taobao, or outlets in Huaqianqbei etc. I also need guaranteed longevity of supply of at least 2-3 years to justify the investment in mass production

I was hoping for official guidance from ST, but that doesn’t appear to be forthcoming.

 

[Windows]

​@alw 

 

Don't forget to mark a post in this thread, as the answer.

 

[db16122]

For STM32MP1, the dram selection would be DDR3/LPDDR3/LPDDR2

For STM32MP2, the dram selection would be DDR3/DDR4/LPDDR4

So the best choice should be DDR3 to fit all the needs. Right now DDR3 is quite popular product online

Search results for: DDR3 DRAM – Mouser

存储器 | 集成电路（IC） - DigiKey

What is the density your project usually used for DDR3? 4Gb or 8Gb?

[Windows]

For STM32MP1, the dram selection would be DDR3/LPDDR3/LPDDR2

For STM32MP2, the dram selection would be DDR3/DDR4/LPDDR4

So the best choice should be DDR3 to fit all the needs. Right now DDR3 is quite popular product online

Search results for: DDR3 DRAM – Mouser

存储器 | 集成电路（IC） - DigiKey

What is the density your project usually used for DDR3? 4Gb or 8Gb?

​@db16122 

 

Yes, you're right!

In order to produce cheap STM32MPU products. One must use EOF DDR memories!

E.g DDR3L and low density LPDDR4 for MP2. Notice that you said DDR3. MP2 does not support that. 

 

I'm focusing on 2GB for LPDDR4. Yesterday I purchased 5 genuine SK Hynix 2GB LPDDR4 from Aliexpress. Around 7 USD each. Because they were EOF.

Edit:

After I purchased the LPDDR4 2 GB memory, the price went directly up 10 USD. I was lucky!

 

[db16122]

LPDDR4 could be a option to use but the price is really unpredictable

[ethonbrooks0707]

This is a very useful discussion. With DRAM availability changing so often, having a list of validated and readily available memory options for both the STM32MP1 and STM32MP2 families would make long-term product planning much easier. It would also be helpful if ST could regularly update recommended part numbers or publish guidance on compatible alternatives when supply constraints affect the originally qualified devices. That kind of information can save a lot of redesign effort during a supply chain disruption.

[Windows]

Hi ​@ethonbrooks0707 

I don't think ST would do this for us. The best way is to do own research. My suggestion is to buy lots of cheap EOL memories with low density e.g 1GB. They are quite cheap. About 10 USD/each.

[PatrickF]

Worth to directly contact manufacturers, some are willing to test their devices in front of STM32MP.
https://wiki.st.com/stm32mpu/wiki/Validated_DRAM_on_STM32_MPU_portfolio

Usually no surprises as all are covered by JEDEC spec. Just need to carefully check the number of CS which is sometimes unclear or depend on memory revision.

 

DDR obsolescence is a complex story as there is few large players which jump quickly to latest technologies (used in PC, server or phones) and (many) small players which usually give longevity programs for industrial/automotive market if there is enough quantity.

Need to contact them directly to see which one they recommend for the quantity you are planning to use.

 

Regards.