How to operate EMMC at 1.8V while my MCU is at 3.3V?

[Kavana shree]

Looking at the eMMC requirement, it looks like HS-200 mode is limited to 1.8V/1.2V I/O levels. (From STM32H7 MCU Reference manual)

 

HS200 Bus Speed Mode

The HS200 mode offers:

• CLK frequency up to 200MHz Data rate – up to 200MB/s

• 4 or 8-bits bus width supported

• Signaling levels of 1.8V and 1.2V

So I am assuming that if I want to be able to run in HS200 mode on my design, I need to connect VCCQ(I/O pwr on eMMC) on the eMMC and VDD on the MCU to 1.8V, correct??

But I have other peripherals which should work at 3.3V. so can't provide 1.8V to MCU​ VDD. I may have to use voltage translator only between MCU and MMC memory. I am not finding voltage translator for MMC which has 8bit data line, 1 command line, 1 reset line,1 clock line and DS line. What is the alternative Solution?

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[Tesla DeLorean]

What are you're actual band-width requirements here?

Where is the data coming from, where is it going too?

I suppose the alternative would be to use discrete buffers, or bank a secondary transceiver to carry the D4-D7 and have them controlled with the D123_DIR.

If I had 200MBps requirements I'd be looking at a quad core A9 with direct emmc interface..

[Kavana shree]

150MBps is the bandw​idth requirement. Data is coming from PC to MCU to EMMC and vice versa.

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What is that buffer ? Any transceiver part name for ​8bit MMC? What is the operation voltage?