Please recommend the lowest power MCU supporting the highest SD Card data transfer rate.

[HKPhysicist]

Dear ST Support,

• I am looking for an ultra low power ST MCU supporting
• the highest data transfer rate on an external SD Card.
• I also need recommendation on a compatible SD Card Connector to match your recommended MCU.
• Ultra low power is mandatory because my design is a portable device.

 

Yours faithfully,
Timmy

[mƎALLEm]

Hello ​@HKPhysicist ,

Asking STM32 Sidekick:

“Please recommend the lowest power STM32 MCU?”

Answer:

Summary

Interpreting “lowest power” as the lowest typical current in the device’s lowest-power mode, the best recommendation is STM32L412C8T6. It was identified with a typical lowest-power supply current of 0.01 µA, a 1.71 V to 3.6 V supply range, and a typical run-mode current of 70 µA/MHz.

Detailed Explanation

Recommended part

STM32L412C8T6

Metric	Value
Product line	Ultra Low Power
Lowest-power supply current, typ	0.01 µA
Run-mode supply current, typ	70 µA/MHz
Supply voltage range	1.71 V to 3.6 V

Why I recommend it

Among the STM32 parts compared, STM32L412C8T6 is the one identified with the lowest typical supply current in the lowest-power mode at 0.01 µA. If your application spends most of its time sleeping and wakes only occasionally, this is the strongest recommendation from the available data.

Important nuance: “lowest power” can mean different things

If by “lowest power” you mean lowest current in active/run mode, then STM32U5 is also a strong candidate: it can go down to 16.3 µA/MHz in active mode, while also offering 200 nA in standby, 1.4 µA in Stop 3 with 16 KB SRAM, and 4.6 µA in Stop 2 with 274 KB RAM.

If you mean lowest documented shutdown current from the ultra-low-power series documents, STM32U0 is extremely low as well: 16 nA in shutdown without RTC, 30 nA in standby without RTC, 630 nA in Stop 2 with full retention and RTC, and 52 µA/MHz at 48 MHz in Run mode.

Practical recommendation

• Choose STM32L412C8T6 if your priority is the absolute lowest deepest-sleep current from the compared STM32 portfolio.
• Choose STM32U5 if you want a very low-power MCU with especially strong active-mode efficiency and multiple retained-memory stop modes.
• Choose STM32U0 if you want an ultra-low-power option with documented nA-level shutdown and standby figures.

Now, what is the MCU among this list is having the SDMMC interface. The answer is the STM32U5 series (an Ultra Low Power MCU):

https://www.st.com/en/microcontrollers-microprocessors/stm32u5-series.html

Hope that helps.

[HKPhysicist]

Hello,

Thanks for the information.

So, what are the specifications of a SD Card Connector which is compatible with STM32U5 MCU?

I am new to storage technology.  Please share your valuable experiences.

 

Yours faithfully.