Looking for an upgrade from MPC5674F with (much?) more internal SRAM

[ricardofranca]

Hello,

I am looking for a MCU that is similar to the MPC5674F, but with (if possible) 1MB SRAM. While looking at the NXP website, the most interesting alternative I could find was the MPC5777C (though it has 512KB SRAM) and I got puzzled by the MPC5775K, which has much more internal SRAM but, apparently, has no EBI and seems to serve a different purpose. Thus, I have two questions:

i) Is there any interesting model I missed?

ii) What is the meaning of these suffixes (F in 5674, B/E/K in 5775, C/M in 5777)?

Thanks!

Ricardo

[ricardofranca]

Thanks for the additional references. Last question (okay, maybe not...) on this topic: how can we compare the EBI and the QuadSPI in terms of external SRAM access performance? E.g. how can we estimate external memory access latency for a MPC5777C vs. a S32K344?

[davidtosenovjan]

Unfortunately I am not aware we have such analysis. I would recommend to contact memory manufacturer, producing both types, for instance Micron, Infineon, possibly others. They will surely have some comparison. Probably there will be also general scientific articles.

From MCU point of view, either serial multi-wire or parallel bus, both modules are connected to XBAR, both buses are running at certain frequency, over certain amount of wires, both accesses has certain address/data phase, both accesses are memory mapped, so I would guess it could be compared to each other.

[davidtosenovjan]

1) I am not completely sure what are your requirements, but external bus is only present with MPC5777C and MPC5777M.

I could recommend following brochure:

https://www.nxp.com/docs/en/product-selector-guide/BRAUTOPRDCTMAP.pdf

2) These are shortcuts of internal code name, it does not have any deeper meaning.

Regarding are of use, it should be as follows -

Control and Gateway: MPC5746C/48G

Radar: MPC5775K

Safety applications: MPC5744P

Engine Management: MPC5777M / MPC5777C / MPC5746R 

Battery Management and Inverters: MPC5775B/E

[ricardofranca]

Hello David,

My question is a bit vague (sorry!) because I know little about the interactions between the MCU and other system components - all I know is that the MCU needs to read/write data from/to external memory with good performance (thus, we need the EBI) and that I need a couple MB for code and 512KB-1MB for data. In the MCUs without an EBI, is there any efficient solution to communicate with external RAM memories?

Thanks!
Ricardo

[davidtosenovjan]

Newest devices no longer uses external bus, the recent trend is the use of QuadSPI module to in order to connect quad SPI memories (4-wires) or octal SPI memories (8-wires). I would point out the same summary above, but take a look to S32K1 or S32K3 devices.

[ricardofranca]

Hello David,

Last question (well... maybe not the last...) on the topic: how can I compare memory access times of a device that uses an EBI (e.g. the MPC5777C) with the newer ones that use a QuadSPI, such as the S32K358?

Thanks!

Ricardo