LPDDR4/LPDDR4x Confusion

[palpurul]

Hello everyone!

I have been working on an FPGA board with (we think it's an) LPDDR4x RAM board and we recently discovered something that's a bit wierd.

We have the evaluation kit for the FPGA and we assumed it had an LPDDR4x RAM on it because the RTL is set LPDDR4x configuration and the RAM's VDDQ supply is set to 0.6V (it should be 1.1V for the non-x LPDDR4).

This is the part we have on the board:


When I decode the part it shows up as an LPDDR4 RAM and it leads to this part:

MT53E256M32D2DS-046 AAT:B which is an LPDDR4 RAM.

However, the VDDQ is set to 0.6V and RTL only works when we set the IP to LPDDRx.

Are LPDDR4 and LPDDR4x can be used interchangebly by just changing the voltage?

Thanks in advance!

[bigendian]

Issue is Micron specification, output from the decoding, they say lpddr4, while it is lpddr4x (2133 Mhz is lpddr4x), x is mainly an overclocking sign.