If you go to "nxp.com", there's a "Search Bar" at the top. If you type "MCF5281CVM66J" into that (like I did) then the SECOND hit is a document that tells you exactly what that means.
This document says they're directly equivalent. AS WELL, this document says the "J" chips were replaced with non-J ones in 2012, so those chips are really old:
https://www.nxp.com/docs/en/product-change-notice/PCN15413.htm
The above says they went from "J" to "non-J" because:
"In GPCN notice 13959 Freescale announced a portfolio of new parts using a new die-attach material. Freescale is now transitioning back to the previously qualified die attach used in the replacement parts shown above."
If you then google for "site:www.nxp.com MCF5281CVM66J" it brings up this:
http://www.nxp.com/docs/en/product-change-notice/PCN15389.htm
Which says:
ISSUE DATE: 03-Oct-2012
NOTIFICATION: 15389
TITLE: END OF LIFE DUE TO LOW SALES
LAST BUY DATE: 03-Oct-2013
LAST SHIP DATE: 03-Oct-2014
Tom
