Strategies to the Prediction, Mitigation and Management of Product Obsolescence

2.3 CHANGE-NOTIFICATION POLICIES OF MAJOR COMPANIES

The change-notification policies of semiconductor manufacturers vary widely, depending on the individual manufacturer, the company division or manufacturing location, and the customer for the parts.

In an effort to evaluate the uniformity of change-notification policies in industry, a survey of the top semiconductor manufacturers, distributors, and contract manufacturers was conducted. The findings of that survey are summarized in the following sections.

2.3.1 Differences by Manufacturer

Most major manufacturers provide change-notifications in a manner compliant with the EIA/JEDEC specifications (see Section 2.4.1.1), despite the common practice of putting disclaimers on data sheets, which say that the manufacturer is free to make changes or discontinue parts without notice. Changes that could affect reliability or performance are usually sent out 60–90 days in advance, while minor changes, such as marking changes, are usually sent out 30–90 days in advance. Part-discontinuance notices are generally sent out at least six months in advance, although companies with more specialized parts often provide more advance warning. For example, Lattice Semiconductor provides one-year advance notice for last-time buys for its programmable logic devices, per the EIA/JEDEC specification, for parts that are likely to be single-sourced. For extra assurance that customers do not miss a change, some manufacturers, including Fujitsu and Xilinx, ...