AM1808: Problems with Micron DDR MT46H64M16LFBF-5 IT:B

Part Number:AM1808

Hello,

My customer has been using the AM1808EZWT4 with Micron MT46H64M16LFBF-6 IT:B RAM successfully at 150MHz.  The -6 version is no longer available, and they are moving to the -5 version (MT46H64M16LFBF-5 IT:B), which should be the identical part, except maximum speed is 200MHz verses the -6 version of 166MHz.  However, they are not getting reliable communication on the data lines.  (Still running at 150MHz)

Have you seen issues before with similar parts, and are there any suggestions for a CODE change that could help?

Thank you,

Keith N.
AFA OH/wPA