Tool/software:
We have designed a custom board with AM6254 processor and one 32Gb x16 DDR4 SDRAM chip.
The SDRAM runs successfully at 400 MHz but doe not at 800 MHz.
I did measured the clock signals to verify that we are setting the frequency correctly and noticed something surprising.
Since I used a single ended oscilloscope probe to measure the DDR4 differential clock, the voltage measurements are not very relevant but the over 3 times smaller peak-to-peak amplitude of the 800 MHz clock vs the 400 MHz clock is surprising to me. See the oscillograms below:
400 MHz clock
800 MHz clock
Thanks,
Kris