What are other testing/process step that we should do if we where to use the old date code QFPs other than solderability and baking ?
What is the plating composition normally %? lead, % tin etc. I have my policy not to accept the more than 12 months old part, but the supplier wants it 18 mnths..what should I do, the problem is this is the sole supplier
Semi conductor devices last for 5-10 years or more when in use. Since those parts are in stock and are not in use they are considered in good condition. The only concern that you got is how will you process them. We had the same problem before and it's with a fine pitch TQFP and it's more than 12 months from date of manufacture. We baked quantity of 10 using the long bake which is at 40'C 7 days. We run the product and tested the products as per normal testing (ICT, Funtional, Burn-in etc.) and all went well. We encountered some failures and all of them has nothing to do with the QFP. We run 50 and monitored...everything went well. Then we run all 10,000 units of the TQFP's and so far they were fine. This is our experience, maybe others in the forum can give you more info with regards to your other concerns.